v0.2

Added:

• Implemented GET_TREE (i3ipc::connection::get_tree())

Changed:

• Shipping all available payload with workspace and window events (issue #2)
• i3ipc::I3Connection renamed to i3ipc::connection
• Internal refreactoring

Fixed;

• Fixing failed build: Parts of a struct were initialised in wrong order, C99-style designated initialisers did not prevent this from causing an error [mox]
• Minor documentation and code fixies