Modernise lua-archive

[hadess]

Lua 5.2 and 5.3 support, as well as porting to libarchive 3.0.

Untested.

[hadess]

Note that I had to disable the "__gc" functions for the code to work and the tests to pass on Lua 5.3.

I don't think that the existing code should regress on 5.1 or older, but I'm still investigating the problems with newer Lua versions.

[tomprince]

It at least compiles and loads for me.