Merge pull request #372 from jaymzh/mounts_6

Fix linux::filesystem reading of /proc/mounts
Revert "Fix linux::filesystem reading of /proc/mounts"

This reverts commit 144ec4c1e5ee4e881d944456b870cae723ea9b0f.

See OHAI-196
Fix reading /proc/mounts harder

Due to kernel bugs we have to nonblock read.