vdimir

@paskal I removed vendor from this PR and pushed it to separate branch [full-text-search-vendor](https://github.com/vdimir/remark/tree/full-text-search-vendor). I haven't create PR for this separate branch yet, because maybe it is better to keep...

> Another round, I reviewed everything but `search` module as it's a beast on its own. @vdimir please let me know if what I wrote something which makes sense or...

> I should have time tonight to review it thoughtfully. Thanks! I think main issue that I haven't figure out is wrapping store.Interface. Wrapping store with proxy is simple way...

> Excellent job! Few very minor things to fix plus few tests to write, and also please check that it compiles as it doesn't now. After fixing that review notes...

I finally run service after all modification, load bunch of comments like in first post in this PR, seems it works. Should I merge vendor files? Now it is in...

@umputun could you review the code, please?

@umputun , thank you for review! I think I've got general idea and I'm going to rewrite PR reusing my code with respect to your notes. If some additional question...

> @vdimir I would love to have your work incorporated into the next release (1.7.0), please let us know if there is any way to assist you. Thanks for the...

Sorry, I've started refactoring, but haven't enough time to work on it. I really want to finish, but I'll postpone it to the end of month or beginning of next...

I tried to reorganize code according to this comment https://github.com/umputun/remark42/pull/757#issuecomment-720160517 Please, look at the code to check if current understating of `search.Service` and `search.Engine` correspond to your sense. Currently I...