chore (ellipticalFilter, ozpbutton): add tests and modify behavior of ellipticalFilter

Modify the behavior of the elliptical filter such that passing 'false' for the ellipsis option doesn't result in the original text being returned, regardless of length

Add missing tests

Closes #247
Merge pull request #248 from ozone-development/issue-247-elliptical-tests

chore (ellipticalFilter, ozpbutton): add tests and modify behavior of el...