Fixes #546 - cleans up title attribute

- Removes title attribute where it is redundant with a link’s direct
content.
- Adds title attribute to buttons that do not contain text content.
- Rewords footer text mentioning grant to make title attribute
unnecessary.
- Removes title attribute from icons where a parent enclosing link also
had the same title attribute.
- Normalizes title attribute text to capitalize first letter.
Merge pull request #549 from codeforamerica/546-remove-title-attr

Fixes #546 - cleans up title attribute