Make the value to text mapping more similar to singlestat solution.
Adds more tests.
Also, allows string to be mapped to other string besides numeric values.
* tech: investigating karma + jest mix
* tech: migrating tests to jest
* tech: moved anoter test file to jest
* test: migrated two more test files to jest
* test: updated readme and made test fail to verify that it causes CI build failure
* tech: added code coverage for jest tests
* tech: testing codecov coverage
* tech: migrated more tests
* tech: migrated template srv to typescript and the tests to jest
* tech: minor build fix
* tech: build fixes
* build: another attempt at fixing go test with coverage
* table-panel: clickable cell link - draft
* table-panel: clickable cell link - fix link target option
* table-panel: fix undefined columnStyle.link
* table-panel: option to highlight cell with link
* table-panel: render variables for all cells in row
* table-panel: remove cell highlighting
* table-panel: add help for URL field
* linkPopover directive for link info in table panel
* table-panel: add link info popover to cells
* table-panel: use native popover instead directive
* table-panel: link drop refactor, remove unused code
* table-panel: fix unclickable link when drop is opened
* refactoring: minor refactoring to #8738, do not think we need a full blown popover for the links, simple tooltip is enough and more efficient, sadly we do not have a modern tooltip framework, still using old bootstrap 2.3 tooltip
* table-panel: add tests for link rendering