Changed warning check in bitfield warn test
0-width bitfield error checking
Type alignment special cases
Change "int:1" bitfield warning
Initial 0-width bitfield logic
bitfields are correctly aligned on word boundaries

Also added bitfield alignment test
Test for bitfields separated by an anonymous struct
Added bf_pad for anon-padding fields
Added struct/union/enum align function
Partial 0-width bitfields support - breaks other bitfields

We finish bitfield packing with logic for overflowing an int field, but
this breaks most other bitfield cases. Better padding logic is needed.