add a "pattern" prop to the form component

Author: lovasoa

sqlpage/templates/form.handlebars

@@ -60,6 +60,7 @@
                         {{~#if step}} step="{{step}}" {{/if~}}
                         {{~#if minlength}} minlength="{{minlength}}" {{/if~}}
                         {{~#if maxlength}} maxlength="{{maxlength}}" {{/if~}}
+                        {{~#if pattern}} pattern="{{pattern}}" {{/if~}}
                         {{~#if required}} required="required" {{/if~}}
                         {{~#if (or (eq autocomplete false) (eq autocomplete 0))}}autocomplete="off" {{/if~}}
                         {{~#if (or (eq autocomplete true) (eq autocomplete 1))}}autocomplete="on" {{/if~}}