Enabled remote filter in compare dropdowns

Phil Hughesrequested to merge
compare-remote-search into master

What does this MR do?

Adds remote filtering to the compare dropdowns. Previously it would only use local filtering so if the project had more than 100 branches & tags, it wouldn't be able to search them correctly.

Screenshots (if relevant)

Screen_Shot_2017-03-16_at_11.51.07

What are the relevant issue numbers?

Closes #29545 (closed)

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