WIP - adding padding span to last visible row.

currently not working with level setting.
Level expansion now keeps track of last visible row.
Refactored code into timelines helper.
Added a test class for timeline table helper.
refactored hideOnLoad
Teach ng WorkPackagesHelper to format 'currency' type

Still missing L10n support: currently EUR symbol is hard-coded.

User Story # 5225

Signed-off-by: Alex Coles <alex@alexbcoles.com>
Teach #column_data_type to handle CurrencyQueryColumn

Since this class is only available in a plugin, we need to handle
match against its class name as a String. A better long-term solution
should be found for plugins to add their own data type.

User Story # 5225

Signed-off-by: Alex Coles <alex@alexbcoles.com>
Merge pull request #1236 from opf/fix/prototypify_hol

[prototype->jQuery]  Refactored hideOnLoad
Merge pull request #1235 from opf/fix/timelines-space-at-bottome-7249

Fix/timelines space at bottome 7249
Fix travis' ruby version

Because of RVM not supporting Ruby 2.1.0 anymore we need to change the
Ruby version for travis.
Merge pull request #1237 from opf/fix/work-package-costs-plugin-currency-type

Fix/work package costs plugin currency type
Fix circular dependency, make timeline column watchers less expensive
Rename timeline column directive
Add unit tests for timeline column data directive
Fix css class assignment after date changes in timeline comparisons
Fix change-indicating css classes in timeline comparison view
Restore former tl comparison markup (but donate an extra span tag)
Fix css classes indicating changed dates in timeline
Merge pull request #1241 from opf/fix/timeline-comparison-7256

Fix/timeline comparison 7256