Cache mdbook

gnzlbg · gnzlbg · commit 38f88a6286ab · 2019-05-25T11:44:07.000+02:00
diff --git a/.travis.yml b/.travis.yml
@@ -1,7 +1,7 @@
 language: rust
 sudo: false
 rust: nightly
-
+cache: cargo
 install: cargo install mdbook
 script: bash -c "cd reference && mdbook build && mdbook test"
 env:
