fix finding version

Author: aaltat

setup.py

@@ -22,7 +22,7 @@
 Framework :: Robot Framework
 """.strip().splitlines()
 with open(join(CURDIR, 'src', 'robotlibcore.py')) as f:
-    VERSION = re.search("\n__version__ = '(.*)'", f.read()).group(1)
+    VERSION = re.search('\n__version__ = "(.*)"', f.read()).group(1)
 with open(join(CURDIR, 'README.rst')) as f:
     LONG_DESCRIPTION = f.read()