airstore: remove getdeps manifest, getdeps sandcastle integration

Summary:
X-link: facebook/fb303#51

X-link: facebook/folly#2220

X-link: facebook/proxygen#501

X-link: facebook/wangle#233

X-link: facebookexperimental/rust-shed#54

X-link: facebookincubator/hsthrift#132

X-link: facebook/openzl#846

Reviewed By: jamestaylr

Differential Revision: D57985865

fbshipit-source-id: cd99755a533ee297365b74204a0ed10180ce4b80

Author: codyohl