Standardized transition between entry title and body

[triplingual]

As with my alphabetization proposal, I've skipped what seem to be obvious entries not appropriate for blunt standardization. Otherwise, I tried to make sure that the title of an entry is separated from its body by a hyphen wrapped by spaces and that the first word of the body is capitalized.

Here and there, I've deleted a word or two to make the new separation form read better. e.g., Shimmy, around line 73, was written as "Shimmy is a Ruby gem . . ." and I rewrote it as "Shimmy - Ruby gem . . .". I tried to be conservative with these, though my opinion is that entry bodies shouldn't begin with an article if the text makes sense without it.

This PR does not include the alphabetization changes.

[jronallo]

This is great. The list needed a pass over it for standardization like this. This will make the list easier to read and with better examples for what contributed entries should look like.

[triplingual]

Thank you. ✌🏻