git-gui: allow larger width for the commit message field

Users may like to make the main window very wide. In this case, a rather
small size of the commit message field leaves a wide unused space at the
bottom-right. Allow settting the field width to values much larger than
99 characters. In fact, users can set it to extreme values to fill the
entire space regardless of window width: the widget geometry will be
negotiated to be limited to the available space despite the large
requested width.

Signed-off-by: Alexander Shopov <ash@kambanaria.org>

Author: alshopov

lib/option.tcl

@@ -155,7 +155,7 @@ proc do_options {} {
 		{i-0..300 gui.blamehistoryctx {mc "Blame History Context Radius (days)"}}
 		{i-1..99 gui.diffcontext {mc "Number of Diff Context Lines"}}
 		{t gui.diffopts {mc "Additional Diff Parameters"}}
-		{i-0..99 gui.commitmsgwidth {mc "Commit Message Text Width"}}
+		{i-0..9999 gui.commitmsgwidth {mc "Commit Message Text Width"}}
 		{t gui.newbranchtemplate {mc "New Branch Name Template"}}
 		{c gui.encoding {mc "Default File Contents Encoding"}}
 		{b gui.warndetachedcommit {mc "Warn before committing to a detached head"}}