Use <div> instead of <a> for list-group-item class.

This addresses issue #63 regarding mangled output when the
method description contains a hyperlink.
Merge pull request #65 from dwcramer/Issue63

Use <div> instead of <a> for list-group-item class.
Fixed HTML validity, closes #61
Release 0.31.1
Support enums for headers and URI parameters, closes #59
Greatly simplified the resource template
Update changelog