Use "system" ABI instead of "C"

This should fix the problem of Windows requiring the "stdcall" ABI rather than "C" (like on Unix-like systems).
Merge pull request #23 from csherratt/master

Update to compile with the latest std::comm
Update for pkgid
Merge pull request #22 from cmr/pkgid

Update for pkgid
Merge pull request #17 from bjz/fix-abi

Use "system" ABI instead of "C"
New symbols from updated xml spec
Use crate_id instead of pkgid/link
Check type attribute for ull == GLuint64. Fixes #24
Merge pull request #27 from jhasse/patch-crateid

Use crate_id instead of pkgid/link
Merge pull request #26 from jhasse/patch-ull

Check type attribute for ull == GLuint64. Fixes #24
Merge pull request #28 from jhasse/patch-newxml

New symbols from updated xml spec
cargo-lite support
Merge pull request #29 from cmr/master

cargo-lite support
Update to Rust master pt2
Merge pull request #30 from cmr/update-master

Update to Rust master
Add some extra versions
removed do syntax from examples
Merge pull request #33 from HeroesGrave/master

Removed 'do' syntax from examples
fixed for latest rust
Merge pull request #34 from HeroesGrave/master

Fixed for latest Rust