Added rollover extension period

Allows a rollover (e.g. a modified keypress) to be registered even if
the modifier key was released slightly before the modified key
Added missing include in ToggleAction.h
Delay action for use in macros
added delayAction import
Revert "added delayAction import"

This reverts commit ee90dbdd1d13ef17f7f33d3aca30a6599b31c908.
added delayAction import
Support for dual MCP23017 chips
Merge branch 'MPC23017-Support' of https://github.com/barrysims/quickbrownfox-firmware into MPC23017-Support