Consider excluding the patch version & `-(RC|M)\d+` from indexing

[rwinch]

We should consider excluding the patch version, milestone, and RC from the version in the search.

Steps

The steps are outlined in the sub-issues.

Results

Initial Upgrade

Projects should update to 0.4.20 which will contain the change for gh-276 and gh-278.

Going Forward

When releases happened, there might be some stale data (deltas between the two pages) but it wouldn't have no results in most cases. The exception is that there would be no results for the first milestone or first SNAPSHOT of a <major>.<minor> until the next crawl happened.