Add ability to skip translation of specific operators or sets of operators

[ahelwer]

The CLI should expose a --skip parameter accepting a space-delimited list of element names which should not be translated. The names will be drawn from the Name column of the CSV file. In addition, this --skip parameter will recognize some keywords denoting sets of elements - for example the lookalikes keyword would skip all Unicode symbols that are simple contractions of their ASCII counterparts.

Perhaps an --only parameter can also be exposed which, instead of skipping the enumerated elements, only translates those elements.