Remove deprecated version field from bower.json file

[wolfika]

refs #2555

[leggomuhgreggo]

Hey @wolfika never having used bower, I wanted to get a better idea of the landscape in the hopes of heading off any subsequent complications merging this PR might invite. I remembered this discussion #2246 from a while back--doesn't look like it actually bears on this issue, but thought I'd reference it anyhow.

I guess my only remaining concern is how many people might be using on older versions of bower that rely on the version field declaration. Let me know if you have any thoughts on the subject. Definitely leaning towards merging this in.

Thanks

[wolfika]

I would find it rational if Bower used git tags a default fallback for parsing a valid semver version if that could not be done from the bower.json. This is just a speculation, I don't know older Bower releases to that extent, but I would find that logical, some further research required.