.travis.yml in knapsack-1.20.0 vs .travis.yml in knapsack-1.21.0

@@ -1,16 +1,16 @@
 ---
 sudo: false
 language: ruby
 rvm:
-  - 2.0.0
   - 2.1
   - 2.2
   - 2.3
   - 2.4
   - 2.5
   - 2.6
   - 2.7
+  - truffleruby-head
 addons:
   code_climate:
     repo_token: 38686058eed480dd0fcf8bce9015733e0bae88e44e30f4a1ac63df8aec2f86d8
 before_install:
   - "echo 'gem: --no-ri --no-rdoc' > ~/.gemrc"