Adding tests for missing elements.
Moving negative tests to unit tests.
Button selector will now find by default 'Submit' text.
Handling attempted interactions with missing elements.
Added tests for dropdowns and radio groups.
Implemented single-select by value.
Implemented single-select by option text.
Implemented multi-select.
Implemented find-radiogroup.
Implemented selecting radio buttons by value.
Implemented selecting radio buttons by label.