utils.lua: Add an inherits function to ease OO development

This will get used in #1719 to implement lua-side hyper{drive, space,
jump}.
utils: inherits: Add a "name" parameter
Fix compilation with gcc-4.7 by deleting copy constructor/assignment of JobHandle (fixes #2799).
Fix signed/unsigned comparison.
auto-commit: translation updates
auto-commit: translation updates
Merge remote-tracking branch 'origin/lua_inherit'