Auto merge of #2720 - alexcrichton:ignore-nfs-more-often, r=brson
Auto merge of #2720 - alexcrichton:ignore-nfs-more-often, r=brson

Ignore file locks on OSX NFS mounts

We already ignore NFS on Linux so let's do the same on OSX as well.

vojtechkral/cargo,mark-buer/cargo,durka/cargo,tshepang/cargo,tshepang/cargo,sbeckeriv/cargo,sbeckeriv/cargo,AndiDog/cargo,achanda/cargo,eminence/cargo,nipunn1313/cargo,nipunn1313/cargo,mark-buer/cargo,sbeckeriv/cargo,AndiDog/cargo,brson/cargo,AndiDog/cargo,rustyhorde/cargo,tsurai/cargo,rust-lang/cargo,AndiDog/cargo,nipunn1313/cargo,vojtechkral/cargo,tsurai/cargo,achanda/cargo,durka/cargo,brson/cargo,brson/cargo,rustyhorde/cargo,rust-lang/cargo,tshepang/cargo,eminence/cargo,vojtechkral/cargo,mark-buer/cargo,durka/cargo,sbeckeriv/cargo,AndiDog/cargo,mark-buer/cargo,mark-buer/cargo,brson/cargo,rustyhorde/cargo,eminence/cargo,eminence/cargo,tshepang/cargo,rustyhorde/cargo,durka/cargo,tsurai/cargo,brson/cargo,nipunn1313/cargo,tsurai/cargo,achanda/cargo,rust-lang/cargo,rust-lang/cargo,achanda/cargo,tsurai/cargo,vojtechkral/cargo