Rpleth, do not respond to GreenLed and Beep command.

For compat reason we shall not respond to those 2 commands.
Rpleth update.

Update documentation for Rpleth: config doc was moved
to an new rpleth.md file.
Default value for stream_mode is now true.
Documentation.

Move module to namespace. Move end-user documentation (configuration information )to external markdown files.
fix test build
Remove old code + refactoring.

Remove unused code.
Proper namespace. Documentation improvements.
Build modifications.

Coverity shall now scan coverity_scan branch.
Change source for libzmq.