Set a default global state for 'proxy.valid'

1.  We can continue to use OSG 3.5 decorators for the proxy tests:
    it'll be easier to find the 3.5-only tests if we label them uniformly
2.  This is less intrusive than try/except blocks at each of the call sites

Author: brianhlin

osgtest/library/core.py

@@ -45,7 +45,7 @@
 # prefix each key with "COMP.", where "COMP" is a short lowercase string that
 # indicates which component the test belongs to, or "general." for truly cross-
 # cutting objects.
-state = {}
+state = {'proxy.valid': False}  # TODO: Drop 'proxy.valid' after we drop support for OSG 3.5
 
 class DummyClass(object):
     """A class that ignores all function calls; useful for testing"""