Add buildenv.py to gitignore
Rename CWalletInterface to CValidationInterface

It's useful for much more than wallets.
Merge pull request #5098

1d66bbc Add buildenv.py to gitignore (Michael Ford)
Merge pull request #5105

a96d113 Rename CWalletInterface to CValidationInterface (Pieter Wuille)
Merge remote-tracking branch 'bitcoin/master'