Updated the description and using statements in eclipse.txt
Only include link to source if one has been provided

Not all licenses have provided a `source` property, so this check just
prevent an empty `href` in such cases.
Add license sources where missing
Merge pull request #101 from IQAndreas/fix-missing-sources

Add license sources where missing
Use the plaintext formatting of the Artistic License 2.0

Another case where the license was copied from HTML, but had a nicely
formatted plaintext version (this is the last one, I promise).

This time the source was taken from
<http://www.perlfoundation.org/attachment/legal/artistic-2_0.txt>
fix 'using' display in sidebar
remove garbage 'using' link
add HTML::Proofer
tweaks to make html-proofing pass
run html-proofing as part of travis build
make testing instructions match travis build steps
build gh-pages branch on travis
display build status in readme
include list of tools
Merge pull request #105 from github/build-status

Build gh-pages branch
Merge pull request #106 from github/tools

Include list of tools
Merge pull request #102 from github/fix-using

Fix 'using' display in sidebar
Merge pull request #104 from github/html-proofer

Set up HTML::Proofer
Merge branch 'gh-pages' of github.com:waynebeaton/choosealicense.com into waynebeaton-gh-pages
fix indentation of projects using Eclipse