Add magit-gh-pulls magit extension
More explicit lighter for gitflow and github-PR magit extensions
Fix annoying company behaviour in ruby-like languages
Better .spacemacs template
Fixes #166 Lower delay for guide-key

Add configuration variable dotspacemacs-guide-key-delay
Fixes #161 Add Trash/Recycle Bin support
Move Erlang and Elixir in a contribution layer
Simplify inactive modeline
Fix functions prefix in erlang-elixir layer
Remove o-blog extension from syl20bnr contrib

It reduces the number of submodule.
I will just put it in a private layer.
Move syl20bnr contrib to usr sub-directory
Improve log in *Messages* at startup

Replace "contribution layer" by "configuration layer"
Prepend the type of package in logs (pre-extension, post-extension or package).
Remove deprecated elixir-mix from erlang-elixir layer
Pylookup package in python now uses correct directory
Add yasnippet support for all company backends
Merge branch 'develop' (v0.21.0)