Fully support any legal path for perl and associated libraries

[lbe]

I was unable install rperl on a perlbrew implementation that uses the perlbrew's libs feature. perlbrew lib is a way to manage local::lib as part of perlbrew. This allows you to use perlbrew with local::lib that are settable using the perlbrew switch command. Otherwise, one has to muck around with environment variables directly.

The rperl problem is that perlbrew uses a naming convention of "version name"@"library name" as the root name of the local lib. So in my case, the name is "22.1t@std". When rperl passed this path through to Inline:CPP, the '@' was not escaped and the compiler didn't know how to handle the problem.

I ran into this both on Macos and Debian. See the gists at https://gist.github.com/lbe/295e957c910fbc968a56c008f8c508f5 and https://gist.github.com/lbe/83a64b2896c5dec02d9bce65fac44db3 to see the full output.

I think rperl should insure that any path passed via inline is appropriately escape for the operating systems supported by rperl.

Thanks,

lbe