New features:
- Added a new submodule which provides some traits that are very useful for debugging
traitlite.debug.BreakOnRead- initializes debugger when the trait is accessed
traitlite.debug.BreakOnWrite- initializes the debugger when the trait is written to
traitlite.debug.BreakOnChange- takes a function which receives the new value and initializes the debugger if said function returns True
traitlite.debug.BreakOnChangeDelta- takes a function which receives the old and new values and initializes the debugger if said function returns True