Added Max for Live API control device.

Added Live Control Hub.amxd device and the max project with patcher files for the device.

The device is designed to centralise a lot of communication with the Live API. Making the task of building applications that receive information from, or send commands to, the Live API more simple.

Live Control Hub.amxd creates a global dictionary named "m4lc-hub" which stores a lot of information about the current live set, and keeps it updated when changes to the live set are made (there are some exceptions for types of information which can't be continuously updated so easily, e.g if a clip slot has a clip inside it).

To access the dictionary in a max for live monome app create a [dict m4lc-hub] object. Make sure to click the "Init" button on the Live Control Hub device user interface first.

Live Control Hub also creates global send and receive objects which send values to, or receive commands from, other max for live apps. The global send and receive name is "m4lc". Messages from the hub are prepended with "hub values", messages to the hub are prepended with "hub commands". (Happy to change or update the protocol used for sending and receiving messages, also needs documenting).