Add firefox history collector post module

Blocked until #3224 lands.

Verification

- [ ] get a shell through a firefox javascript privilege exploit, like `exploit/multi/browser/firefox_proto_crmfrequest`, using `set TARGET 0` to use a js shell
- [ ] `use post/firefox/gather/history`, run it against the above session
- [ ] you should get a json file containing all the history currently  saved in firefox