Searchbox - Replace submit button with magnifying glass icon

[pigeonflight]

This is what the search box should look like according to the mockup:

This is what it looks like now:

This requires hiding or removing the submit button and adding a magnifying glass icon as in the design.

[pigeonflight]

Plone 5.0 ships with glyphicons-halflings-regular.ttf so it should be acceptable to rely on the search icon that ships with the glyphicons ("\e003").

[pigeonflight]

I've started work on a searchbox branch. This is what it looks like so far:

Will still need to clean up the markup a bit. Here's the first commit: https://github.com/plone/plonetheme.barceloneta/commit/a401f1966eb32cdd5a6270b5be29b29169a19bdd

[draunger]

/Assign me I will do this task

[Rudd-O]

Craft PR and link to issue using markdown. You can also assign yourself (I think if you are part of the org) at the top right corner of the page.

One thing I realized is that the search button doesn't look clickable at all in the mockup. This might be an issue.