update protobuf version to latest (2.5.0).
add parseFrom() methods to the generated object, to mirror static methods created by protobuf.
fix tests for added "parseFrom" methods.
if an error occurs during compilation, exit with an error code, so external tools will know.
Merge pull request #56 from robey/parsefrom

add "parseFrom" and exit(1) on error
Added parseDelimitedFrom to the companion object. Added a test.
Version bump to 1.3.0. Updated Scala to 2.10.2.
Added  a forgotten test. Minor improvements and an UpdateTestResources fix.
Updated README with latest version: 1.3.0.
Added a performance test. Can be used with a profiler.
Unneeded lazy val changed to a def.