Merge branch 'fix-html5-color-inputs' into 'master'

Remove instances of HTML5 input type="color" due to inconsistent browser support

## What does this MR do?

`<input type="color" />` renders differently across browsers.  Reverting to `type="text"` where necessary.

## Screenshots (if relevant)

Safari (top) vs Chrome (bottom)
![Screen_Shot_2016-09-28_at_11.53.02_AM](/uploads/f967ed988320cbd2e4357cdfcfe7a813/Screen_Shot_2016-09-28_at_11.53.02_AM.png)

See merge request !6576

app/views/admin/broadcast_messages/_form.html.haml

@@ -18,11 +18,11 @@
   .form-group.js-toggle-colors-container.hide
     = f.label :color, "Background Color", class: 'control-label'
     .col-sm-10
-      = f.color_field :color, class: "form-control"
+      = f.text_field :color, class: "form-control"
   .form-group.js-toggle-colors-container.hide
     = f.label :font, "Font Color", class: 'control-label'
     .col-sm-10
-      = f.color_field :font, class: "form-control"
+      = f.text_field :font, class: "form-control"
   .form-group
     = f.label :starts_at, class: 'control-label'
     .col-sm-10.datetime-controls

app/views/admin/labels/_form.html.haml

@@ -14,7 +14,7 @@
     .col-sm-10
       .input-group
         .input-group-addon.label-color-preview  
-        = f.color_field :color, class: "form-control"
+        = f.text_field :color, class: "form-control"
       .help-block
         Choose any color.
         %br

app/views/projects/labels/_form.html.haml

@@ -14,7 +14,7 @@
     .col-sm-10
       .input-group
         .input-group-addon.label-color-preview  
-        = f.color_field :color, class: "form-control"
+        = f.text_field :color, class: "form-control"
       .help-block
         Choose any color.
         %br