This commit implements the two serde traits for the libstd `OsStr` and
`OsString` types. This came up as a use case during implementing sccache where
we're basically just doing IPC to communicate paths around. Additionally the
`Path` and `PathBuf` implementations have been updated to delegate to the os
string ones.
These types are platform-specific, however, so the serialization/deserialization
isn't trivial. Currently this "fakes" a newtype variant for Unix/Windows to
prevent cross-platform serialization/deserialization. This means if you're doing
IPC within the same OS (e.g. Windows to Windows) then serialization should be
infallible. If you're doing IPC across platforms (e.g. Unix to Windows) then
using `OsString` is guaranteed to fail as bytes from one OS won't deserialize on
the other (even if they're unicode).
* move to cargo clippy instead of using the clippy plugin
fixes#729
* non-exectable scripts must be run with `sh`
* don't build serde in the clippy travis job
* only run clippy tests if installing clippy succeeds
* why is travis so picky?
* no more serde_codegen
* serde_test_suite_deps has no features
* don't use empty loops, llvm optimizes them to undefined behaviour
* abort the clippy job when clippy lints are triggered
* use caches on travis to speed up builds
* why are we even using `travis-cargo`?
* need to reinstall clippy frequently due to nightly updates
* command line tools are hard
