Merge pull request #1 from 1000Springs/master

Updating live with latest changes
Bug Fix

Text in simple search combo box was not visible
Added feature type to Location model so it gets displayed on sample-site
pages.
Added robots.txt in the right place this time
Added read-count filter to confident_taxonomy view, so read counts <= 5
are not included in taxonomy visualisation.
Fixed microbial diversity visualisation pie chart so segments and
percentage values shown are correctly weighted.
Reduced Cache-Control expiry time from 7 to 1 days for chemistry and
taxonomy data.
Merged in changes from master
Added hidden input fields with max-range values to search side-bar to
get it working.
Corrected alignment of image and map.
Added link to large version of image on samplesite page
Reduced distance between circles in status bar so 'Complete' doesn't get
cut off.
Added title (mouse hover text) containing concentration ppm to chemistry
bubble chart.
Changed chemistry bubble chart to show full element names instead of
chemical symbols.
Corrected height of microbial diversity visualisation side bar
containing wikipedia-sourced info.
Changed 'hot' colour on simplesearch page from yellow to red in IE
(since IE does not support multi-colour gradient backgrounds).
Changed title on location search page from 'Map Search' to 'map search'
to make it consistent with other pages.
Merged in changes from master
Added graceful degradation for browsers that don't support SVG (IE8 or
less). Minor tweaks to get layout looking ok in Opera, Safari and IE8.
Fix for option alignment on indented location select boxes