Show article contributors using git history

[RedWolves]

Ported from jquery/2012-dev-summit#44

A crude version of this was working in the nanoc build using the github metadata, where we'd hit the github API for whoever was specified in that metadata, an obviously subpar solution. We should read the file's git history and display the full list of contributors who've actually worked on the file (ranked?).

Not sure what to display, exactly, however, for contributors, as I don't think we want to be hitting the GitHub API during build anymore.

We may still have to grandfather in the "original contributors" using some metadata, for people who wrote articles in other sources and donated to the learn site, but didn't make the initial commit contribution themselves (as in the case of the original jQuery Fundamentals content)

Looking up contributor history might be useful for other sites besides learn, so this might be something we could incorporate into grunt-jquery-content perhaps.

[RedWolves]

@gnarf37 said "Check out git log --format='%aN' filename | sort | uniq - All that data is already stored locally in git"

[RedWolves]

@Krinkle said "Slightly faster (since sort can already detect adjacent duplicates):

git log --format='%aN' filename | sort -u

Alternatively include counts, from many to few:

git log --format='%aN' filename | sort | uniq -c | sort -nr

It looks like a second sort is needed, as uniq only filters out equal lines that follow each other.

Then in what ever script, split by new line, trim, and split by space with limit of 2 (the second sort could be omitted if it is sorted in the script instead).
"

[RedWolves]

@gnarf37 said: Although... It would be pretty nice to actually use github accounts instead of author names/emails.

[RedWolves]

@johnkpaul said: @ajpiano Do you not want to hit the github API at all? We can get the username from the email addresses in the commits and then write to a local cache so that we'll only need to hit the API for new users. I think that we should be incorporating this into grunt-jquery-content.

[RedWolves]

@ronchalant said: is at least the initial target for this the http://stage.learn.jquery.com/ site?

[RedWolves]

@ronchalant said: @ajpiano - would you think this should be added to the post object created by the wordpress-parse-post-flex helper?

[RedWolves]

@ronchalant said: I committed one pull for this that retrieves the git information. I didn't use the sort/uniq/etc. piped commands, preferring instead to dedupe in the JS code. This should make the code more platform independent for Windows builds.

Some guidance on how the author information would be added to the post content (e.g. in "parse-markdown" helper for .md files). I would assume an unordered list would be added somewhere?

[ajpiano]

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