Refine diagnostics when push and rebase fail

[gberche-orange]

Would need further diagnostics for operators:

• git logoutput with the last few commits prior to the push
• git diff HEAD origin/master

   2019-10-29T10:56:32.60+0000 [APP/PROC/WEB/0] OUT 2019-10-29 10:56:32.609  INFO 13 --- [nio-8080-exec-8] c.o.o.c.b.o.o.git.SimpleGitManager       : [paas-secrets.] commit push
   2019-10-29T10:56:33.31+0000 [APP/PROC/WEB/0] OUT 2019-10-29 10:56:33.319  INFO 13 --- [nio-8080-exec-8] c.o.o.c.b.o.o.git.SimpleGitManager       : [paas-secrets.] staged commit:  added:[coab-depls/x_d60c
0d1d-00a9-4592-87d5-f462823c9bff/enable-deployment.yml] changed:[] deleted:[]
   2019-10-29T10:56:33.32+0000 [APP/PROC/WEB/0] OUT 2019-10-29 10:56:33.327  INFO 13 --- [nio-8080-exec-8] c.o.o.c.b.o.o.git.SimpleGitManager       : [paas-secrets.] commited files in commit 5b411b9717cf23a
0d39957c382602ddc4557a818 1572346593 -----p
   2019-10-29T10:56:33.32+0000 [APP/PROC/WEB/0] OUT 2019-10-29 10:56:33.329  INFO 13 --- [nio-8080-exec-8] c.o.o.c.b.o.o.git.SimpleGitManager       : [paas-secrets.] Preparing to push: behind commits=0 ahea
d_commits=1
   2019-10-29T10:56:33.32+0000 [APP/PROC/WEB/0] OUT 2019-10-29 10:56:33.329  INFO 13 --- [nio-8080-exec-8] c.o.o.c.b.o.o.git.SimpleGitManager       : [paas-secrets.] pushing to master ...
   2019-10-29T10:56:33.58+0000 [APP/PROC/WEB/0] OUT 2019-10-29 10:56:33.584  INFO 13 --- [nio-8080-exec-8] c.o.o.c.b.o.o.git.SimpleGitManager       : [paas-secrets.] pushed ...
   2019-10-29T10:56:33.58+0000 [APP/PROC/WEB/0] OUT 2019-10-29 10:56:33.584  INFO 13 --- [nio-8080-exec-8] c.o.o.c.b.o.o.git.SimpleGitManager       : [paas-secrets.] Failed to push with status [REJECTED_NON
FASTFORWARD]
   2019-10-29T10:56:33.58+0000 [APP/PROC/WEB/0] OUT 2019-10-29 10:56:33.584  INFO 13 --- [nio-8080-exec-8] c.o.o.c.b.o.o.git.SimpleGitManager       : [paas-secrets.] pull and rebasing from origin/master ...

   2019-10-29T10:56:34.60+0000 [APP/PROC/WEB/0] OUT 2019-10-29 10:56:34.608  INFO 13 --- [nio-8080-exec-8] c.o.o.c.b.o.o.git.SimpleGitManager       : [paas-secrets.] rebased from origin/master
   2019-10-29T10:56:34.60+0000 [APP/PROC/WEB/0] OUT 2019-10-29 10:56:34.608  INFO 13 --- [nio-8080-exec-8] c.o.o.c.b.o.o.git.SimpleGitManager       : [paas-secrets.] re-pushing ...
   2019-10-29T10:56:35.78+0000 [APP/PROC/WEB/0] OUT 2019-10-29 10:56:35.784  INFO 13 --- [nio-8080-exec-8] c.o.o.c.b.o.o.git.SimpleGitManager       : [paas-secrets.] re-pushed ...
   2019-10-29T10:56:35.78+0000 [APP/PROC/WEB/0] OUT 2019-10-29 10:56:35.784  INFO 13 --- [nio-8080-exec-8] c.o.o.c.b.o.o.git.SimpleGitManager       : [paas-secrets.] Failed to re-push with status [REJECTED_
NONFASTFORWARD]
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT 2019-10-29 10:56:35.790  WARN 13 --- [nio-8080-exec-8] c.o.o.c.b.o.o.git.SimpleGitManager       : [paas-secrets.] caught java.lang.RuntimeException: faile
d to push: remote conflict. pull rebased failed:org.eclipse.jgit.transport.FetchResult@24d996dd
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT org.eclipse.jgit.api.RebaseResult@691c7f44
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT java.lang.RuntimeException: failed to push: remote conflict. pull rebased failed:org.eclipse.jgit.transport.FetchResult@24d996dd
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT org.eclipse.jgit.api.RebaseResult@691c7f44
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT     at com.orange.oss.cloudfoundry.broker.opsautomation.ondemandbroker.git.SimpleGitManager.pushCommits(SimpleGitManager.java:400) ~[cf-ops-automation-bro
ker-core-0.29.0.jar!/:0.29.0]
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT     at com.orange.oss.cloudfoundry.broker.opsautomation.ondemandbroker.git.SimpleGitManager.commitPushRepo(SimpleGitManager.java:332) ~[cf-ops-automation-
broker-core-0.29.0.jar!/:0.29.0]
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT     at com.orange.oss.cloudfoundry.broker.opsautomation.ondemandbroker.git.RetrierGitManager.lambda$commitPushRepo$4(RetrierGitManager.java:50) [cf-ops-au
tomation-broker-core-0.29.0.jar!/:0.29.0]
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT     at net.jodah.failsafe.Functions.lambda$supplierOf$14(Functions.java:309) ~[failsafe-2.0.1.jar!/:2.0.1]
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT     at net.jodah.failsafe.Functions.lambda$resultSupplierOf$11(Functions.java:283) ~[failsafe-2.0.1.jar!/:2.0.1]
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT     at net.jodah.failsafe.internal.executor.RetryPolicyExecutor.lambda$supply$0(RetryPolicyExecutor.java:67) ~[failsafe-2.0.1.jar!/:2.0.1]
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT     at net.jodah.failsafe.Execution.executeSync(Execution.java:117) ~[failsafe-2.0.1.jar!/:2.0.1]
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT     at net.jodah.failsafe.FailsafeExecutor.call(FailsafeExecutor.java:319) ~[failsafe-2.0.1.jar!/:2.0.1]
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT     at net.jodah.failsafe.FailsafeExecutor.run(FailsafeExecutor.java:231) ~[failsafe-2.0.1.jar!/:2.0.1]
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT     at com.orange.oss.cloudfoundry.broker.opsautomation.ondemandbroker.git.RetrierGitManager.commitPushRepo(RetrierGitManager.java:48) [cf-ops-automation-
broker-core-0.29.0.jar!/:0.29.0]
   2019-10-29T10:56:35.79+0000 [APP/PROC/WEB/0] OUT     at com.orange.oss.cloudfoundry.broker.opsautomation.ondemandbroker.git.PooledGitManager.commitPushRepo(PooledGitManager.java:69) ~[cf-ops-automation-b
roker-core-0.29.0.jar!/:0.29.0]