Translate synsets across lexicons via ili about wn HOT 1 CLOSED

I'm going with the following (thanks for the suggestion, @fcbond):

• Synset.translate() and Sense.translate() return a list of Synset or Sense translations, respectively, through the Synset's ILI
• Word.translate() returns a dict mapping a Sense to the list of Words that are translation of the sense

>>> wn.synsets('緑茶')[0].translate(lexicon='ewn:2020')
[Synset('ewn-07951392-n')]
>>> wn.senses('緑茶')[0].translate(lexicon='ewn:2020')
[Sense('ewn-green_tea-n-07951392-01')]
>>> wn.words('緑茶')[0].translate(lexicon='ewn:2020')
{Sense('wnja-07935152-n-33498'): [Word('ewn-green_tea-n')]}

One other problem was what to do with synsets without an ILI. Initially I thought of raising an error, since it's not the case that there are no translations in the resource, but that we cannot check because of the lack of ILI. But this wouldn't make sense for Word.translate() because there might be other senses whose synset does have an ILI and I wouldn't want the error to block those. So for this first implementation it will return an empty list for any sense/synset without any ILI, which is the same behavior as when there is an ILI but no entities in the target lexicon linked to the ILI. Users who care about the distinction would need to check the ILI themselves.

from wn.