Updates to t3 to display tooltips and additional information under timeseries names.
First iteration of CDID endpoint for multi-timeseries graphs.
Now scans the taxonomy and finds the data, but doesn't yet return it.
Now returns data.
Now returns a map.
Now has some caching functionality.
Additional code to parse more dataset information.
Updated with additional dataset parsing.
Tweaked Alpha Content pending Rob's next update.
Added CDID list.
Merge branch 'multi-series' into dataset

Conflicts:
	src/main/resources/files/app/templates/t3/t3.html
Added the ability to download data using a list of CDIDs instead of a
list of URIs.
Dataset page download buttons for timeseries. Small fixes on download endpoint
Updated with the latest from Huddle.

Conflicts:
	src/main/resources/Alpha content master.xlsx
Modified timeseries multiplier handling to work with values less that 1.
Taxonomy update with latest Alpha Content spreadsheet.
Fix for selection of a null date key if the first timeseries has no
value.
Merge branch 'dataset'

Conflicts:
	src/main/java/com/github/onsdigital/generator/datasets/DatasetContent.java
	src/main/java/com/github/onsdigital/util/XLSXGenerator.java
	src/main/resources/files/app/components/sparkline/sparkline.js
	src/main/resources/files/app/templates/t5/t5.controller.js
	src/main/taxonomy/businessindustryandtrade/changestobusiness/businessbirthsdeathsandsurvivalrates/datasets/businessbirthsanddeaths/data.json
	src/main/taxonomy/businessindustryandtrade/itandinternetindustry/datasets/ecommerceandictactivity/data.json
	src/main/taxonomy/businessindustryandtrade/manufacturingandproductionindustry/datasets/outputoftheproductionindustries/data.json
	src/main/taxonomy/businessindustryandtrade/tourismindustry/datasets/overseastravelandtourism/data.json
	src/main/taxonomy/economy/data.json
	src/main/taxonomy/economy/economicoutputandproductivity/datasets/grossvalueadded/data.json
	src/main/taxonomy/economy/environmentalaccounts/datasets/atmosphericemissionsgreenhousegasemissions/data.json
	src/main/taxonomy/economy/governmentpublicsectorandtaxes/researchanddevelopmentexpenditure/datasets/expenditureonrdintheuk/data.json
	src/main/taxonomy/economy/inflationandpriceindices/datasets/producerpricesinflation/data.json
	src/main/taxonomy/employmentandlabourmarket/peopleinwork/labourproductivity/datasets/labourproductivity/data.json
	src/main/taxonomy/peoplepopulationandcommunity/birthsdeathsandmarriages/lifeexpectancies/datasets/lifeexpectancyenglandandwales/data.json
	src/main/taxonomy/peoplepopulationandcommunity/birthsdeathsandmarriages/lifeexpectancies/datasets/lifeexpectancyuk/data.json