bump version from 0.2.2 to 0.3.0

New Functionality
* Can get port by id

Safety Improvements
* `JackHandler` functions now take & instead of &mut
* `JackHandler` now requires `Sync`

Misc
* Functionality exposed through modules instead of global jack:: namespace
* Added more testing, though still flaky

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "jack"
-version = "0.2.2"
+version = "0.3.0"
 authors = ["Will S. Medrano <will.s.medrano@gmail.com>"]
 description = "Real time audio and midi using safe JACK bindings."
 documentation = "https://wmedrano.github.io/rust-jack/jack/index.html"