remove reference to boxsizing.htc file for bootstap-ie7.

Please don't merge unless you are Fran. This is to remove boxsizing.htc not loading issue. I believe we don't need to load  boxsizing.htc do to using Respond.js later in the document.

In testing I see no side effect which makes is a better option then:  https://github.com/ORCID/ORCID-Source/pull/641