Make emlink.py import-safe. Fixes an issue where python multiprocessing.py enters an infinite loop throwing errors 'Attempt to start a new process before the current process has finished its bootstrapping phase.' when running other.test_static_link. See http://stackoverflow.com/questions/18204782/runtimeerror-on-windows-trying-python-multiprocessing .
Move bullet library build code to runner.py so that it can be shared between test_the_bullet in test_core.py and test_static_link test_other.py.
Fix other.test_static_link on Windows by using CMake instead of configure to build zlib and bullet.
Merge pull request #1814 from juj/fix_test_static_link

Fix test static link