Reorganize : add buttleEvent.

A lot of things in this commit.
Most important : buttleData is split in 2 class => buttleData and buttleEvent.
Also renamed a lot of signals (mostly for nodes and connections), in order to be more clear.

No features added in this commit !
Fix bug when reset value of paramInt and paramDouble.
Param modifications.

Update all params of a node when just one is modified.
Merge branch 'develop' of github.com:buttleofx/ButtleOFX into develop

Conflicts:
	buttleofx/gui/paramEditor/qml/ParamRGBA.qml