* mode initializers should call text-mode-init to register ccallback
for s->offset and s->top_offset, and other generic stuff.
* this is error prone, should simplify this with base_mode property and
keep unmapped windows lingering to get rid of ModeSavedData handlers
* pass ModeDef pointer to mode_probe functions
* add extensions field to mode structure
* rename ascii mode to binary mode
* rename mode variables and fields to more specific names
renamed canonize to canonicalize
added crude support for ~user -> /home/user
added win32 specific stuff in basename
added C-/ as an alias for C-_
some cosmetics, moved code
create files with mode 0644 in raw_save_buffer
untabified, removed redundant spaces
modified code generators to the same effect
