Updated to build with 1.0.0-beta

[lambdacat]

The tests don't work, but that seems unavoidable since the test
feature is unstable (so extern crate test simply won't compile).

[jdm]

Looks likes

src/lib.rs:315:44: 315:54 error: use of unstable library feature 'convert': waiting on RFC revision
src/lib.rs:315             match load_png_from_memory(buf.as_slice()) {
                                                          ^~~~~~~~~~

would also prevent beta compatibility right now, right?

[metajack]

Comment out the #[bench] tests or remove them? The extern crate test seems only used for those. Or perhaps there is a stable formulation for benchmark tests we can use?

[lambdacat]

According to the wisdom of the #rust irc channel, there is no beta-stable alternative at the moment. So I've commented out the benchmarks, and now the build is passing.

[jeffparsons]

FWIW I've just built and tested one of my toy projects (a local branch of https://github.com/slashgrin/lifelike updated to build with the 1.0.0beta rustc) against 6585178, and what little of the rust-png API I'm exercising appears to be working just fine.

[jdm]

Looks good to me!