.travis.yml in pr-0.0.6 vs .travis.yml in pr-0.0.7

@@ -1,10 +1,19 @@
+# required for ruby below 2.3
+dist: trusty
 language: ruby
-
+before_install: gem update bundler
 rvm:
+  - 2.7.1
+  - 2.6.6
+  - 2.5.8
+  - 2.4.10
+  - 2.3.8
+  - 2.2
+  - 2.1
+  - 2.0
+  - 1.9.3
+  - 1.9.2
   - 2.0.0
   - 1.9.3
   - 1.9.2
-
-  - rbx-19mode
   - jruby-19mode
-  - ruby-head