feat: autogenerate readme from command help

.travis.yml

@@ -5,5 +5,15 @@ env:
   - DOKKU_VERSION=v0.19.0
 install: make setup
 before_script: sudo sysctl -w vm.max_map_count=262144
-script: make test
+script:
+  # Check that README etc. is up to date
+  - >
+    make generate;
+    if [[ $(git diff) ]]; then
+      echo "Please run `make generate`";
+      git status --short;
+      git diff;
+      exit 1;
+    fi
+  - make test
 after_failure: make report