Rename all icon files to expected wsu-spine-icons-regular format

The spine.css is looking for files that are named wsu-spine-icons-regular.*,
but the files that exist in the repository are wsu-icons-regular.*. This is
allowing some fonts to work because they are loading from nbj.me still, but
others are not working because they cannot be found.

Related #47, which the next commit will address
Use fonts hosted at repo.wsu rather than nbj.me

To avoid the extra DNS lookup on page requests, and to ensure general
stability, we should be loading all font resources from repo.wsu.

Closes #47
Merge pull request #48 from washingtonstateuniversity/font-fix

[PR] Rename font files to wsu-spine-icons-regular.*, serve from repo.wsu