no default shortcut for isabelle.reset-font-size -- avoid conflict with unsplit-current;

--- a/NEWS	Tue Nov 05 16:41:19 2013 +0100
+++ b/NEWS	Tue Nov 05 18:16:16 2013 +0100
@@ -98,8 +98,9 @@
 toplevel theorem statements.
 
 * Action isabelle.reset-font-size resets main text area font size
-according to Isabelle/Scala plugin option "jedit_font_reset_size"
-(cf. keyboard shortcut C+0).
+according to Isabelle/Scala plugin option "jedit_font_reset_size" (see
+also "Plugin Options / Isabelle / General").  It can be bound to some
+keyboard shortcut by the user (e.g. C+0 and/or C+NUMPAD0).
 
 * File specifications in jEdit (e.g. file browser) may refer to
 $ISABELLE_HOME and $ISABELLE_HOME_USER on all platforms.  Discontinued

--- a/src/Tools/jEdit/src/jEdit.props	Tue Nov 05 16:41:19 2013 +0100
+++ b/src/Tools/jEdit/src/jEdit.props	Tue Nov 05 18:16:16 2013 +0100
@@ -212,8 +212,6 @@
 isabelle.increase-font-size2.shortcut=C+EQUALS
 isabelle.reset-continuous-checking.label=Reset continuous checking
 isabelle.reset-font-size.label=Reset font size
-isabelle.reset-font-size.shortcut2=C+NUMPAD0
-isabelle.reset-font-size.shortcut=C+0
 isabelle.reset-node-required.label=Reset node required
 isabelle.set-continuous-checking.label=Set continuous checking
 isabelle.set-node-required.label=Set node required