Added color picker field

[bfintal]

Added type color, uses WordPress' native color picker and created a new template for the new field.

I don't know where to put the initializing js though, so I added it to the template file. I also used jQuery('[id="{{ data.attr }}"]') instead of just specifying the ID via #{{ data.attr }} since that did not work when the shortcode is edited multiple times since the first initialization no longer exists on the succeeding call.

We need the color option for our: Page Builder Sandwich

[danielbachhuber]

We should only load these if a colorpicker field type has been used.

[bfintal]

Revamped how the color field was included, now included the same way as #146

Much cleaner now

[mattheu]

Can just do this.$el.find() here

[mattheu]

Looking great

One small comment on the styling. This rule .media-frame a { border-bottom: none } in media-views.css is removing the border - which is a little annoying.

I think the only solution is to add a style to the shortcake CSS to fix this

[bfintal]

@mattheu all done :) Also added in the attribute checker. Might be beneficial if that function was ported over to the Shortcode_UI class so other fields can use it.

[bfintal]

@mattheu Good catch on the bottom border, I must be going blind 👍

[danielbachhuber]

👍 Thanks for your work on this, @bfintal

[mattheu]

Might be beneficial if that function was ported over to the Shortcode_UI class so other fields can use it.

+1 see #173