Flint 1.1.1 - Minor changes and fixes

- [x] Upgrade to Bootstrap 3.1.1
- [x] Thinner font styles
- [x] Fix override conflict with .widgets.widgets-footer
- [x] Register defaults for custom footer options
- [x] Implement two footer elements
 - Custom Footer Area
 - Site Credits
- [x] New actions!
 - `flint_open_entry_header_404` / `flint_close_entry_header_404`
 - `flint_open_entry_header_$type` / `flint_close_entry_header_$type`
 - `flint_open_cat_title` / `flint_close_cat_title`
 - `flint_open_tag_title` / `flint_close_tag_title`
 - `flint_open_$term_title` / `flint_close_$term_title`
 - `flint_open_archive_title` / `flint_close_archive_title`
 - `flint_entry_meta_above_$term` / `flint_entry_meta_below_$term`