gpg task fails on Debian stable

[Scaramush]

Can be fixed by adding --no-tty parametr to shell task:
shell: 'gpg --no-tty --batch --keyserver {{ item }} --recv-keys {{ rvm1_gpg_keys }}'

[thbar]

Note to @sfgeorge - I wonder if this is already covered by some tests at the moment (anyone can look into it, not just you :P)