Switch to PPA package for diesel CLI installation

Author: jtgeibel

.travis.yml

@@ -31,7 +31,6 @@ env:
 
 install:
   - script/ci/cargo-clean-on-new-rustc-version.sh
-  - which diesel || cargo install diesel_cli --vers `cat .diesel_version` --no-default-features --features postgres --debug
 
 before_script:
   - diesel database setup --locked-schema
@@ -40,9 +39,12 @@ addons:
   chrome: stable
   postgresql: "11"
   apt:
+    sources:
+      - sourceline: 'ppa:jtgeibel/rust-backports'
     packages:
       - postgresql-11
       - postgresql-client-11
+      - diesel-cli
 
 matrix:
   fast_finish: true

script/ci/cargo-clean-on-new-rustc-version.sh

@@ -3,7 +3,7 @@
 set -e
 
 manual_stamp_file=target/ci_manual_stamp
-manual_stamp=9 # Change this to force a clean build on CI
+manual_stamp=10 # Change this to force a clean build on CI
 
 if [ -f $manual_stamp_file ]; then
     if echo "$manual_stamp" | cmp -s $manual_stamp_file -; then