Made Relese NG entity file an optional argument

In D4698#203936, @Stan wrote:

Just realised I'm an idiot and you need a way to specify the location because you don't want to put the rng in the mod folder (since you're probably gonna zip it afterwards) and it won't be there on the CI either.

Deleted the middle directory scripts in entity.rng's location. Didn't made it eligible, by argument, to avoid directory creation in case of not existence.

In D4698#203928, @Stan wrote:

~~ Sadly I'm not sure I can set you as author. There seem to be a way but I dunno if trac and phab support it https://stackoverflow.com/questions/2107719/how-to-set-author-for-svn#2107898 ~~

EDIT: Seems it's only for files.

It's been a complete overhaul of the file, but it is working. Now it receives the modules' location and name as parameters.

Added a new diff with the flag -U3000 as suggested on IRC.

On lines 23 and 25 of the patched file, there is a call to the sys' module exit() function. That usage is discouraged because redefines the exit built-in in Python's interpreter when importing the module containing such import from the interactive Python interpreter. The usual way to handle exit statuses is to make the main function to return those values (def main() -> int) as integer values and handle them in the calling of the main function like so: