Formalized the procedure of registering new filters in FilterContext,...

Formalized the procedure of registering new filters in FilterContext, optimized the number of aggregation queries, fixed issue with invalid checkbox options shown when loading the search page with non-empty filters.
14 jobs for new-search in 33 minutes and 48 seconds (queued for 3 seconds)
Status Job ID Name Coverage
  Build
passed #1374851
build

00:12:19

 
  Prepare
passed #1374852
prepare

00:00:59

 
  Test
passed #1374858
dev setup tests

00:11:28

passed #1374854
gui linting

00:04:49

passed #1374856
gui tests

00:05:26

passed #1374857
install tests

00:06:45

passed #1374853
python linting

00:06:32

passed #1374855
python tests

00:20:29

81.0%
 
  Release
manual #1374859
allowed to fail manual
deploy dev
manual #1374860
allowed to fail manual
deploy prod beta
manual #1374861
allowed to fail manual
deploy prod test
manual #1374864
allowed to fail manual
pypi package
manual #1374863
allowed to fail manual
python package
manual #1374862
allowed to fail manual
release latest image