HDFStore.__contains__ bug due to use of regex

[bsdfish]

HDFStore.contains takes the node name and uses it as a pattern to search for. That crashes if the name of the node isn't a valid regex, for example "node1(()" and doesn't function correctly if the node name is a valid regex but doesn't necessarily match itself.

[jreback]

easy fix, the reason for the regex is to allow you to pass w/o the leading '/'.....
out of curiosity, why would name a group like that?

[jreback]

and pytables gives a NaturalNameWarning on this in any event (it still works though)

[jreback]

fixed

[bsdfish]

I'm caching values w/ keys based on function calls, so perfectly valid names are 'foo(3)' or maybe 'bar("(()")' if someone ever decides to pass a string "(()" into the function. I can work around using hashes, etc but this makes it easy to follow.

[jreback]

sounds good
btw u can suppress the natural name warning easily if u want (see test_pytables.py)