Fix show "2b" text instead of proper glyphicon

I'm using babel and webpack with less-loader to bundle all resources maybe this will cause this issue.

less/glyphicons.less

@@ -32,8 +32,8 @@
 }
 
 // Individual icons
-.glyphicon-asterisk               { &:before { content: "\2a"; } }
-.glyphicon-plus                   { &:before { content: "\2b"; } }
+.glyphicon-asterisk               { &:before { content: "\002a"; } }
+.glyphicon-plus                   { &:before { content: "\002b"; } }
 .glyphicon-euro,
 .glyphicon-eur                    { &:before { content: "\20ac"; } }
 .glyphicon-minus                  { &:before { content: "\2212"; } }