Parse escaped spaces in makefile dependencies

This means that if a project has a file with a space in the name it will
properly have its freshness calculated as opposed to always having it as a
candidate to be rebuilt.

Closes #648
auto merge of #663 : alexcrichton/cargo/issue-648, r=brson

This means that if a project has a file with a space in the name it will
properly have its freshness calculated as opposed to always having it as a
candidate to be rebuilt.

Closes #648
Don't always run doc tests for the root package

When using `cargo test -p`, be sure to run only the doc tests for the package
actually being tested.

Closes #660
auto merge of #661 : alexcrichton/cargo/issue-660, r=brson

When using `cargo test -p`, be sure to run only the doc tests for the package
actually being tested.

Closes #660
Make sure dev-deps are compiled for examples

Examples are classified as binaries, but do not have the `test` flag set on
their Profile. They do, however, have their environment set to `test`. Be sure
to place them into the `tests` bucket so they have development dependencies
available for their compilation.