Store the jetty lock file in the permdir by default

In general, I feel the xwiki-jetty package should store as fewer files as possible outside its own area.

The subject of this proposal is the lock file which is currently stored in /var/tmp by default, but I feel it would be safer and more bulletproofed (sometimes you don’t have the right to write in /var/temp) to change the default to store it in the permdir (at the root feels fine to me, but I can understand if someone thinks it should have a dedicated folder).

There might be something I don’t get here, but why preferring the permdir and not the configured temporary directory ( for this file, since it’s temporary?

Yeah, I was kind of expecting this comment but forgot to give more information about that since that’s another discussion we probably need to have: right now the temporary folder used by this package is based on asking Java for an available temp file (so it’s not stored in its own folder which IMO is not great but at least it should always end up in a writable location) and it’s not easy in the bash script to know what it’s going to be.