Rename language_server and swiplserver

[EricZinda]

Pretty consistent feedback has been that calling the Prolog side of this "language server" is confusing since that term is used in a pretty standard way for the component that connects an IDE and a programming language.

Best alternative for the Prolog predicate is: machine_query_interface and for the Python library is PrologMQI

from the original suggestion post:

"You might want to think of using the word “interface”, then, since in most OO languages that means “a thing you can use without knowing the implementation details”. I’m also put in mind of GDB/MI, gdb’s machine interface protocol, so that’s another point there. And, since this is effectively a replacement UI for Prolog’s classic REPL toplevel, perhaps call the toplevel predicate machine_query_interface and call the various other-language libraries “Prolog-MQI”? That reinforces that you’re only exposing half of the language (the query half, not the programming half), and a command line like

swipl /path/to/program.pl -t machine_query_interface makes it incredibly clear what you’re getting (a way to send queries to the Prolog engine for this particular program) and how it’s supposed to be used (connect it to another piece of software). “Prolog-MQI” is also very googleable, which more software really ought to take into account"

[EricZinda]

This has been fixed and the term is now "machine query interface"

[EricZinda]

Fixed and changed