make gremlin query keys are case insensitive

[masco]

for example g.v().Has('IPV4' 'x.x.x.x') and g.v().Has('Ipv4', 'x.x.x.x') are equal.

[nplanel]

yeah go for it :) In the implementation you just need to upcase the string input from the user for metadata key and compare it ... seems simple but lots of step are involved and filters too please add an unit test as well

There will be a lots of small change for that, here you can see (just a quick look) where you need to do some changes :

gremlin/traversal/flows.go:372 topology/graph/traversal/traversal.go:1039 topology/graph/traversal/traversal.go:297 topology/graph/traversal/traversal.go:640 topology/graph/traversal/traversal.go:700 ....

[masco]

https://github.com/skydive-project/skydive/pull/1264