Enhanced aliases.

Lets aliases be specified over multiple rows.
remove redundant doall
fix indentation.
Merge pull request #118 from MastodonC/feature/extended-aliases

Enhanced aliases.
wip: add properties comparison page back.
Load all properties into the table.
Fix selection of properties.
Add route for getting all properties.
Filter sensors for properties.
Get date ranges.
Fetch measurements.
Plot multiple properties.
- todo: deselection should not clear existing measurements but should filter them out instead
- tofix: sensors don't load on refresh
Add upper and lower ts to sensors table.
Store entity_id in history as part of sensor id.
Fix typeahead lookup and chart's legend.
Show when fetchign data.