Added condition for 'linux.'  Based on 'mac' conditition, but points to linux version of simplestore under /usr/lib - on Ubuntu/debian at least.
'Executing' the string resulted in error, needed to be quoted. Replaced with '1+1' test, as seen at http://www.zorba.io/documentation/latest/zorba/build/build_and_install#testing_install
'Link' to zorba library, versus using an absolute path.
Merge pull request #4 from kefo/master

zorba-node on linux