[tripleo] stepping down from TripleO core

Hello, As you might know or notice, I recently joined a different company, and my focus has been changed. I'm still involved in the OpenStack community but I may no longer be involved in TripleO. To clarify my status I've removed myself from TripleO core. # Please be aware that I'm removing myself from release liason, # someone from the core team might want to replace me, though # I don't think there may be multiple releases created in the future. I'd like to thank all members in the team (current members and ex-menmbers) for your great collaboration and work in the project. Thank you, Takashi Kajinami