replaced "initial" with "text"

I believe this is what we want.  [mdn](https://developer.mozilla.org/en-US/docs/Web/CSS/user-select) doesn't specify which is the default.  Chrome works with `initial`, but firefox doesn't.

src/modules/modal.less

@@ -32,10 +32,10 @@
   -moz-border-radius: 5px;
   border-radius: 5px;
   
-  -webkit-user-select: initial;
-  -moz-user-select: initial;
-  -ms-user-select: initial;
-  user-select: initial;
+  -webkit-user-select: text;
+  -moz-user-select: text;
+  -ms-user-select: text;
+  user-select: text;
 }