[vendor] Import XCPretty.
[vendor] Use custom XCPretty printer when building an Xcode project.
[vendor] Actually add our custom XCPretty printer.
[sim] Make app launch again with Xcode 5.1.

Fixes http://hipbyte.myjetbrains.com/youtrack/issue/RM-365
[sim] Get simulated app PID as int instead of NSNumber.

Related to http://hipbyte.myjetbrains.com/youtrack/issue/RM-365
libmacruby -> librubymotion
improve build system in order to compile spec files in parallel as much as possible

So far, RubyMotion has two phase in compile when run spec (1. compile app files, 2. compile spec files).
it make idle cpu cores when finished to compile app files (before starting to compile spec files).
add 'rake crashlog:device' task, wording/UX is still a work in progress
update README
2.18