- Implement page string names for dialog lumps
- Create special new GZDoom name space for ZSDF
- add usdf_gzdoom spec document
- fixed: restored original behavior with negative conversation id's for the original strife dialog lumps
- reposition the binary strife fix in a more appropriate location
- add compatibility fix for negative numbers in responses in USDF/ZSDF (don't know if it's actually necessary)
