Remove deprecation of Press Key keyword

[emanlove]

The Press Keys keyword was introduced to replace Press Key. Press Key in turn was deprecated but I (Ed Manlove failed to remove). Its been noted that both keywords use different underlying methods for sending or pressing keys and either one will work in differing situations. So instead of removing Press Key, it has been reinstated as a library keyword.

I would like to eventually understand the difference and educate users about when to use one over the other. Possibly rename or combine the two in a future release.

[emanlove]

Fixed in #1891