Label definition during macro expansion problematic for local/anonymous labels

[envenomator]

1. During a macro expansion, a local label like @Local currently doesn't have a 'scope'. If the same macro is expanded twice within the same caller's scope (before any global label, between two global labels, or after the last global label in a file) - a collision will occur.

2. During a macro expansion, a anonymous label will immediate collide if the caller is also using anonymous labels 'surrounding' it's expansion. Something like this is problematic:

   .macro test
   @@:
   ld a, 0
   .endmacro

@@: ld a, 1 test jp @b; <= this will jump to the local label IN THE MACRO DEFINITION

This behavior is unintended and needs to change.
Going forward, only local labels will be allowed in a macro body. Global labels were not allowed before and will continue to not be allowed. Local labels will be allowed and internally be extended with a 'macro expansion ID' to create a unique expansion scope that will also work during recursive macro invocations.

[envenomator]

50b9cce