Add notification .proto file.
Change protobuf message name.
Add callback registering.
Add service for receiving signal.
Add tests for registering signals.
make more compact debug info by truncating strings
Merge remote-tracking branch 'kali/bug/more-compact-debug' into develop
Properly use AES in CTR mode
Use indexes to fetch keys.
Fix wrong iv test to account for new form of iv.
allow absolute paths to config.load
change docstring comments to use sphinx style
Merge remote-tracking branch 'kali/bug/allow-absolute-paths2' into develop
Merge remote-tracking branch 'drebs/feature/2341-use-indexes-to-store-and-fetch-keys' into develop

Conflicts:
	src/leap/common/keymanager/keys.py
Remove keymanager from this repository.
add data files: testing certificates
Merge remote-tracking branch 'kali/bug/add-data-files' into develop
Remove deps on soledad and python-gnupg.
Merge remote-tracking branch 'drebs/feature/2683-move-keymanager-to-leap_client' into develop
Move symmetric encryption code to leap.soledad.