Fix demo_example.html

Also replace tabs with spaces and add links as shortcuts to the test functions.
Remove declarative bindings

These were only an experimental work-in-progress, and are likely to change
significantly as a result of the proposed API changes regarding TimeSources.
Removing them now to simplify the process of making those API changes.
Remove templates

These have been dropped from v1 of the spec.
Merge pull request #49 from steveblock/timeSourcesCleanup

More time sources cleanup
let length interpolation be independent of the expected length types
let length addition be independent of the expected length types
remove explicit initialization for zero point
Remove explicit initialization from toCssValue and fix bug in default interpolation case.
replace 'percent' label with '%' in length objects.
replaced length toCssValue with generic version
Make fromCssValue generic.
review changes
best test evar
fix indentation and test.