Move glob tests to a run-pass test

The normal unit tests cannot change the current working directory because it
messes with the other tests which depend on a particular working directory.
auto merge of #9170 : alexcrichton/rust/flaky-fileinput, r=erickt

The glob tests cannot change the current working directory because the other tests (namely the fileinput ones) depend on the current working directory not changing.
auto merge of #9151 : catamorphism/rust/rustpkg-target-specific-subdirectory, r=brson

r? @brson As per rustpkg.md, rustpkg now builds in a target-specific
subdirectory of build/, and installs libraries into a target-specific
subdirectory of lib.

Closes #8672
rustpkg: Cleanup