Update README.md

Add a link to Bootstrap a11y theme
Merge pull request #23 from weboverhauls/master

adding close button to list of alert and modal fixes
Merge pull request #19 from bassjobsen/patch-1

Update README.md - add a "Other Resources" section with a link to the a11y bootstrap theme.
Merged with weboverhauls-master
Merge pull request #24 from weboverhauls/master

minor punctuation and formatting