Add {{SERVER_JARFILE}} option instead of (something).jar

[Teslicek]

When using pterodactyl, I sometimes need to change the jarfile (and java flags) for the server.

That's why I suggest to add a RESULT option, something like "Pterodactyl", that would basically replace (something).jar for {{SERVER_JARFILE}}.

Pterodactyl automatically replaces {{SERVER_JARFILE}} with the name of the file you add in the panel.

[encode42]

There's already a "Pterodactyl" option in the advanced memory options modal, I'll look into replacing the filename input if said option is enabled.

[encode42]

Added in the v2 rewrite

(issue will be closed when it's released)

[TekExplorer]

@encode42 Would recommend doing the same thing with the memory arguments, to use whatever the pterodactyl server has, and sets -XX:MaxRAMPercentage=95.0 which will use at most 95% of the available ram.