Fix display of alarm (especially in GUI mode, where pl2 would not be shown)
Note that setclock() does not work for UTC clocks :(
Consistently use negative return values to indicate errors.
Properly free memory used by strdup() as shown in strsep(3).
Explicitly compare pointers to not NULL
Revert threaded implementation for statusbar(), it will not be necessary and introduces extra dependencies.
Add functionality to change the log file, using the 'L' key.

Typing is continuous, but echoing is limited to 1 character per second
because (buffered) getting and echoing characters is done once per second.

Link readpin against guifuncs.o
Do not leak logfilename.
Advertize the 'L' key.