travis does not report build error

[odanoburu]

this issue is (mostly) for documentation purposes.

the travis build uses the Setup.* scripts, and these call the GF compiler with the --no-pmcfg flag; therefore all errors that would happen in this phase will not be reported. (an example of this is 3cb24d9)

now, the Setup.* scripts call the compiler this way because it would take ages for it to compile the RGL otherwise (or are there other reasons?). but this issue can be solved by having travis call the script discussed in #118 with only the languages that have been modified, which shouldn't take too long (unless it's French :P)