Add ^ and $ special command targets to select lowest and highest

numbered windows, from Raghavendra D Prabhu.

cmd.c

@@ -863,6 +863,10 @@ cmd_find_window(struct cmd_ctx *ctx, const char *arg, struct session **sp)
 		wl = s->curw;
 	else if (winptr[0] == '!' && winptr[1] == '\0')
 		wl = TAILQ_FIRST(&s->lastw);
+	else if (winptr[0] == '^' && winptr[1] == '\0')
+		wl = RB_MIN(winlinks, &s->windows);
+	else if (winptr[0] == '$' && winptr[1] == '\0')
+		wl = RB_MAX(winlinks, &s->windows);
 	else if (winptr[0] == '+' || winptr[0] == '-')
 		wl = cmd_find_window_offset(winptr, s, &ambiguous);
 	else

tmux.1

@@ -408,11 +408,15 @@ otherwise the current window in
 is chosen.
 The special character
 .Ql \&!
-uses the last (previously current) window, or
+uses the last (previously current) window,
+.Ql ^
+selects the highest numbered window,
+.Ql $
+selects the lowest numbered window, and
 .Ql +
 and
 .Ql -
-are the next window or the previous window by number.
+select the next window or the previous window by number.
 When the argument does not contain a colon,
 .Nm
 first attempts to parse it as window; if that fails, an attempt is made to
@@ -1126,6 +1130,7 @@ This command works only from inside
 .Ic choose-tree
 .Op Fl s
 .Op Fl w
+.Op Fl u
 .Op Fl b Ar session-template
 .Op Fl c Ar window-template
 .Op Fl S Ar format
@@ -1151,6 +1156,9 @@ If
 .Fl w
 is given, will show windows.
 If
+.Fl u
+is given, the tree is uncollapsed by default.
+If
 .Fl b
 is given, will override the default session command.
 Note that
@@ -1639,7 +1647,7 @@ is the same as using the
 .Ic last-pane
 command.
 .It Xo Ic select-window
-.Op Fl lnp
+.Op Fl lnpT
 .Op Fl t Ar target-window
 .Xc
 .D1 (alias: Ic selectw )
@@ -1655,6 +1663,11 @@ are equivalent to the
 and
 .Ic previous-window
 commands.
+If
+.Fl T
+is given and the selected window is already the current window,
+the command behaves like
+.Ic last-window .
 .It Xo Ic split-window
 .Op Fl dhvP
 .Op Fl c Ar start-directory