ENH: add happi search widget from atef

[klauer]

Description

Add more user-friendly happi search widget from atef.

Motivation and Context

We made these for atef, we may as well upstream them to happi.
We need to find a home for the ophyd device tool as well - likely not happi.

How Has This Been Tested?

Where Has This Been Documented?

Screenshots (if appropriate):

[klauer]

(Rebasing on happi master; less because I want to work on this PR and more because I want to see the effect of the line-profiler 4.1.1 release)

[klauer]

We might have some updates from atef on these widgets. Perhaps we merge and then follow up?

[tangkong]

It does look like there have been some changes. I'm happi to merge those changes in later.

This addition does make me wonder if it's worth the time to figure out how to separate happi[ui] from happi[core]. There's not too much to this GUI currently, but I kinda liked the pure-code-ness of happi.

also if I have to add qt tests to happi I'm gonna cry

[klauer]

I suppose we could have happi-qt instead? I'm fine with that I guess, but having it get out of sync would be a bit painful

[tangkong]

I do think having the viewer in this package will be helpful. Maybe we reconsider happi-qt or happi[qt] when we accrue more substantial ui elements. For now I'm ok with this

[ZLLentz]

Should we merge this before or after the upcoming tag?

[klauer]

This may be ready to merge? @ZLLentz @tangkong

[tangkong]

I'm ok with merging this, with the understanding that we'll have to merge in the updated version from atef and/or create happi-qt later on.

[tangkong]

closes #221