Set RLIMIT_CORE to zero. For some reason the core file size is huge.

Ticket: CM-3346
Reviewed By:
Testing Done: ifupdown2 sanity

I dont see a real reason for a core file to debug ifupdown2 problems
currently. Will re-enable core file generation when i root cause the
issue.

sbin/ifupdown

@@ -13,6 +13,7 @@ import argparse
 import ConfigParser
 import StringIO
 import logging
+import resource
 from ifupdown.ifupdownmain import *
 from ifupdown.utils import *
 
@@ -422,7 +423,7 @@ def main(argv):
 
 if __name__ == "__main__":
 
-
     # required during boot
     os.putenv('PATH', ENVPATH)
+    resource.setrlimit(resource.RLIMIT_CORE, (0,0))
     main(sys.argv)