Optional dependencies support

Allow to inject optional dependencies, see #20.

Internal: add Appveyor build.

Pass IComponent context to ConfigurationProvider

Incorporates #19 - breaking API change.
Dependencies upgraded.

Update dependencies

Update to latest Quartz.Net and Common.Logging.

v 1.3.0

Job wrapper removed, scopes are tracked internally.

v.1.1

Remove JetBrains annotations dependency, fixes #3

Minor updates

Updated InterruptableJob wrapper;
Synced with Autofac 3.5.0;