Update to latest goflow

[rowanseymour]

No description provided.

[rowanseymour]

@nicpottier I've found one more little thing to tweak in goflow - disallowing != for number and date fields and catching that at parse time too.. but just wanna check.. we really can't support that in ES?

[nicpottier]

Can't I don't know for sure, but don't currently. Would have to do some research to figure all that out and whether there is a reason we don't support it now.

[codecov]

Codecov Report

Merging #222 into master will decrease coverage by 0.11%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #222      +/-   ##
==========================================
- Coverage    47.8%   47.69%   -0.12%     
==========================================
  Files          82       82              
  Lines        7204     7204              
==========================================
- Hits         3444     3436       -8     
- Misses       3233     3237       +4     
- Partials      527      531       +4

Impacted Files	Coverage Δ
search/search.go	89.91% <0%> (-3.51%)	⬇️

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[rowanseymour]

Merging this for now as it's a lot more correct than it was. Also note there's a drop in coverage because some evaluation errors are now technically impossible because they're caught at the parser stage.