malloc(0) may return NULL, so only assume that is an error if allocating
more than zero.
Fix AIX warnings.
Declaration in header should be extern.
Flag to flush all key bindings from Rob Paisley.
Add XAUTHORITY to update-environment, requested by Andreas Kloeckner.
Whoops, get the logic the right way round.
+.
Don't allow last and active window to become the same - a very bad move
when the active window is closed and freed. Reported by sthen@.
Update man page for update-environment.
Show more window and pane flags in list-* output, and put layout on the
same line.
+.
There is somewhere that WINDOW_HIDDEN is getting set when it shouldn't
be and I can't find it, but the flag itself is a useless optimisation
that only applies to automatic-resize windows, so just dispose of it
entirely.

Fixes problems reported by Nicholas Riley.
+.
If VISUAL or EDITOR contains "vi", configure mode-keys and status-keys
to vi.

Based on a diff from martynas@, previously requested by a couple of
other people.
+.
Using working directory always, from Vivien Mallet.
+ SF requests.
Moar.
And moar.
Another.