Implemented show result.
Merge pull request #230 from angathorion/show-result

Show result
Adding a new show field for filters.
Exclude data store from controller code coverage.
Implement Utils::make_option.
Add tests to check equality tests for filter predicates.
Add tests to check for predicate equality.
Test equality for show queries.
Implement capturing the filters from the show query.
Add tests and indicate boundary cases for the show query.
Fix broken test for filter columns.
We only have binary predicates, so the value is not optional.
Increase code coverage.
Improve code coverage by not using the switch-case.
Improve code coverage.
Improve code coverage further.
Lint fix.
Add placeholders for undo queries.
Add quick-and-dirty undo command parsing.

Conflicts:
	You-NLP/query_parser.cpp
	You-NLP/query_parser.h
Technically, when we ask for something in either {ascending|descending} order it is actually {nondecreasing|nonincreasing} order because of the possibility of equal keys.

Conflicts:
	You-Controller-Tests/internal/query_executor_builder_visitor_tests.cpp