The player name is stored in whoami[], which is length 80 in most games
(1024 in rogue5). Only the first 10 chars were used to create
file_name, because that buffer is the same length. Increasing the size
of file_name to 256 permits using all of whoami.
The name is also no longer truncated to 20 chars when writing the log.
All games should now be able to handle 79-character names without
collisions. Anything more would break save compatibility.
A buffer called curpurch, which stores a description of an item in a
trading post which the player might be interested in, was only 15
bytes. It was overflowing into oldrp, a room pointer, leading to
segfaults. The size of curpurch has been increased to LINELEN*2,
which matches the size of prbuf, which is returned by inv_name and
then strcpy()'d to curpurch. As long as nothing overflows prbuf it
should be safe now.
NOTE that this breaks savefile compatibility.
