refactor(limitTo): no need for all those checks if we use slice

Closes #10537
feat(limitTo): ignore limit when invalid

BREAKING CHANGE: limitTo changed behavior when limit value is invalid.
Instead of returning empty object/array it returns unchanged input.

Closes #10510
docs(tutorial/12): fix path to jquery in bower

Closes #10504
docs(guide/index): Link to starter options

Add a link to a comparison spreadsheet of alternative generators, examples,
tutorials and seeds that one can use to get started on a new Angular project.

Closes #10526
perf(ngStyleDirective): use $watchCollection

Since we are simply watching a flat object collection it is more performant
to use $watchCollection than a deepWatch...

Closes #10535
docs(guide): fix spaces

Closes #10539