Help dialog for search queries

[jrozner]

Currently we have a help modal that pops up or hotkeys in the timeline. It would be nice to have a modal that describes all the options for the search queries and how to use it as right now you either need to guess or know. I don't think we need to tie it to a hotkey, so we don't need to worry about hotkey collision for help but maybe have an icon next to the search bar to pop it up?

Are there technical issues with implementing it this way? If needed we could always add this into the normal help modal but I think having a separate one would probably be a bit nicer to keep things separate.