Free cbindgen from rustc-internal dynamic lib dependencies#135

Merged

eqrion merged 3 commits intomozilla:masterfrom staktrace:standalone

Feb 21, 2018

+238-34

Commits on Feb 21, 2018

Replace syn with standalone-syn to avoid dragging in rustc internal lib dependencies
staktrace
committed
Bump libc version to work around Amanieu/parking_lot#60
staktrace
committed
Since cbindgen now only compiles with the nightly compiler, update travis.yml accordingly
staktrace
committed