Characterize - add tristate controls (unicode-org#170)

* Adding ICU4C running collation tests - first try

* Cache ICU4C binaries in GH and locally, only if they don't exist

* Install JSON-C dependency if not installed at beginning of CI or e2e script

* Fix bash if condition syntax

* Tristate added for characterizations

* Fix clearing of the checks

* Add tristate for all tests states

* Revise handling of widgets for characterized sets

* Update count of selected

* remove unneeded

* Undo unneeded

* Undo change in coll.cpp

* Revise characterizations, fixing bad labels

* Fix comment typos

* Fixing some Python errors in test reports

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Co-authored-by: Elango Cheran <[email protected]>