UPGRADING-TO-0.90.txt

Version 0.90 of the library has changed the API significantly in order to save flash and RAM.
The main change is that other than USBComposite, all pre-declared object instances have been
removed.

When upgrading to 0.90 or higher, you will have to make a number of changes to your code.

1. Use a single include file instead of USBHID.h, USBMIDI.h, etc.:
    #include <USBComposite.h>
    
2. Declare all instances other than USBComposite. This includes instances of plugin classes
   like USBHID as well as of HID profiles like HIDKeyboard (which need an instance of USBHID).
   
3. Note that USBHID is now a class (for consistency with other class names) and there is no
   USBHID instance. You need to declare an instance, e.g.:
    USBHID HID;
   and replace calls to USBHID.* with calls to HID.*.

4. Replace USBHID_begin_with_serial(...) with HID.begin(CompositeSerial,...) where HID is your
   instance of USBHID.