RLS VSCode forces recompilation of my cargo libraries

[lugehorsam]

Prior to using the vs-code extension, cargo build would not recompile unchanged dependencies. After I installed the extension, cargo build does recompile these dependencies.

Note that this is a more aggressive issue than https://github.com/rust-lang-nursery/rls-vscode/issues/353 as it does not just occur on startup, but every time I build.