Fix parsing bug for Firefox

Previously if you have model which was string that Firefox could not
parse with `new Date` then you'd end up with an invalid date.

This change fixes that by parsing the date with provided
`parseDateFunction`
Example code was not properly closed.
Merge pull request #59 from joseph-ortiz/patch-1

Example code was not properly closed.
Readme note on lack of updates and upcoming replacement directive
Merge branch 'master' of github.com:adamalbrecht/ngQuickDate
Merge pull request #57 from RoleModel/fix_firefox_parsing

Fix parsing bug for Firefox