Hide geolocation button by default

- Geolocation button was showing up when geolocation was not supported
(IE8). This hides the button by default and displays it only when
geolocation is supported.
- Removes unneeded ERB.
Moves geolocation button above input field

Fixes #503 - Moves geolocation button on inside location filter input
field above
the input field. This makes it so when the geolocation button is hidden
initially the
layout doesn’t change when the geolocation button shows up.
Merge pull request #575 from codeforamerica/default-hide-geolcation

Default hide geolcation