Add support for "et al."

[engeir]

Similar to #98, it would be nice if "et al." in citations was recognized.

[grantlemons]

vs. is another one that we should support

[grantlemons]

and etc.

[ghorsey]

I took a screenshot of the issue:

[elijah-potter]

I've drafted #473 that should resolve this issue. Let me know if it does not.

[hippietrail]

Can it not query the dictionary when at a period to see if there's an entry for the combination of the group of letters preceding the period plus the period itself and if so treat the combination as an abbreviation rather than the end of the sentence. The alternative would seem to be a growling list of special cases in the logic.

But some such can occur at the end of a sentence, which leads to ambiguity which might need more heuristics.