Remove 'refresh' button from navbar

Superfluous functionality that clutters the navbar.

Most decent browsers have an easy-to-find refresh button anyway, and there's
always "Ctrl-F5"
Syntaxic sugar
minor formatting
cleanup sidenav css and remove superflouous elements
change showurl to a compact external target=_blank link
fix remove span/a nesting
metric tooltips work better below the item
Rename modals to metric search (modal)
Help user search for metrics when none are displayed
s/Find/Search/
Replace version link with settings modal

Settings includes list of all backends, and logic for storing of the error
messages from the last refresh. Refresh button also given.
correct issues when no errors stored in system
Use same logic for 'now' button as for prefill field on relative time
Correct formatting and validation for absolute time

moment.js deprecation warning and related issues: https://github.com/moment/moment/issues/1407
Zoom to Selected functionality

For graphs with range sliders, when the window.location.hash is changed, create
a link to set the bounds of the range slider to the start and stop of the url.
This will allow the selected area to be re-queried, usually at a higher
resolution.

Also added check to ensure time period less than 600 is not inadvetently
selected.
update search link in rspec
update search link in rspec
update zoomtoselected logic
Known ports are so much better for capybara debugging
Ensure Settings.backends enumeration only occurs when Settings.backends exist