This library was developed by Chris Hulbert to be compiled on CCS or IAR for MSP430 and is available on gitHub.This library provides the following Arduino like Application Interfaces:
Program Execution Macros: setup() and loop()
I/O Macros: pinMode(), pinBit(), digitalWrite(), and digitalRead()
Although there is No support from Arduino IDE but CCS(Code Composer Studio) is not that bad either even for beginners. There is lot of tutorial materials available to help people kick start using it. Plus it has the max code limit 16KB which is boon for hobbyists.
However there are better libraries from Functionality Point: MSPhere which is much more mature and used.