[#43] Build council's list using the data on the dataset

This makes it possible to update the data and add new councils just by updating
the dataset on OpenSpending. There's no need to change the code.
[#43] Rename datasetName -> councilName
[#43] Don't show Reporting Type's buttons if there's only one available

For example, we have data for "Budget" and "Actual" for Tignere, but Yaoundé 2
and Yaoundé 6 just have "Budget".
[#43] Upgrade OpenSpendingJS

This was needed to get the fix at
https://github.com/openspending/openspendingjs/pull/64 . We're using the
64-deprecated-unescape branch, but should move to master whenever that's
merged.
[#43] Fix council title in their budget page
[#43] Fix Tignere's budget links
[#41] Use dropdowns instead of buttons for selecting years
[#41] Style the years' dropdown
Hide the reporting type's buttons by default

We only show them if the current dataset supports it, so we avoid "flashing"
controls in datasets that don't support it.