Remove useless getType on CommandDescriptor
Refactor to ease the usage of non object based commands
Use a specific invoker for object based descriptor
Make the logic of GroovyCommandManager reusable
Improve the default logging properties by providing the .level default value that a user can modify to get more info
Doc improvements:
- make the developers chapter only care about command as classes
- the developer chapter now covers also the Java language
- the groovy chapter now covers the script command and the inter command API
Rewrite the pipeline section of the shell interaction chapter
Move the command context section after the style section in the developers chapter
Improve the shell pipeline section
CRASH-189 : Use command script return value only when it is explictly returned
Improve propagation of flush/close in the pipeline
Minor cleanup
Move the CommandCreationException to the spi package
Avoid to use inner class that carry a lot of complexity
Update bouncycastle to 1.49

This commit updates bouncycastle to 1.49 and use the standard artifact
names. The openssl support has moved to a separate artifact, 'bcpkix'
which has been added as well.

Issue: CRASH-188
Refactor stuff a bit to simplify
- rename LoggerRenderable -> LoggerRenderer
- have MemoryUsageLineRenderer to be package protected
Improve developer documentation
Update asciidoctor to 0.1.4
Update to Byteman 2.1.4.1