Make plugin settings searchable in IDEA

[dlsniper]

At the moment no plugin options are searchable from the settings filter and this should be improved.

As an example see: #2082 (comment) or search for gopath to same effect.

[dlsniper]

I think this is related to: #1909 (might be a duplicate from what I can understand in that ticket).

[zolotov]

No, it's not