Merge pull request #76 from mgage/release/2.7

Fix stupid $ typo
Replace webwork2-dev with webwork2 in README
update pointer for release notes
Fixed uninitialized variable
Merge pull request #77 from goehle/upgraded2.7

Fixed uninitialized variable
Correct instructions for crendentialfile
Add locally hosted smoothness themes
Merge branch 'release/2.7' of https://github.com/openwebwork/webwork2 into release/2.7