Git: Disallow quotes for branch name

At least on Windows it fails.

Change-Id: I2e119bf47b468a9f881184ad26fa9fbd10f16124
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>

src/plugins/git/branchadddialog.cpp

@@ -62,6 +62,7 @@ public:
                                    "|\\\\"   // no backslash
                                    "|//"     // no double slash
                                    "|^[/-]"  // no leading slash or dash
+                                   "|\""     // no quotes
                                    )),
         m_localBranches(localBranches)
     {