Merge branch 325 into dev

re #325
Merge branch 394 into dev

re #394
Merge commit 'a05fb1f5648f048f2c3fb79155a65d5557cbfc2e' into dev

Merging updates from HSCIC:
- Connection pools
- Highcharts integration
- Replace Grunt with Gulp
- Jasmine tests
- Loading view fixes

re #440
Fix cutting on charts

re #440
Fix "Reset All" functionality

re #440
Remove element loading spinner and simplify masonry
Replace "fetch_observations" with "update_dimension"

re #440
Fix customise bar

re #440
Don't set the measure query param for the connection url if the element's measure attribute is null

re #440
Get rid of masonry

re #450
The element model isLoaded() function takes into account the dimensions that actually needs to be updated

re #449
re #448 Fix black bar in import process and spinner.
Use Karma test runner
Fix gulp build scripts and update paths
Merge commit '1dba19c0e42ebf8239bb176db6e6b99b1c73b5c4' into dev
Include visualisation documentation as an HTML file that lives in the dataseed-visualisation repo

re #443
Update the element filter sort attribute with the latest format

re #443
Move all the documentation in dataseed-visualisation

re #443
Add the Element doc section; remove a duplicated line in the documentation TOC; s/dataseedapp/getdataseed/; build dataseed js and css

re #443
Fix a typo