[Tests] up to node v12, v11.14, v6.17

Author: ljharb

.travis.yml

@@ -2,12 +2,13 @@ language: node_js
 os:
  - linux
 node_js:
-  - "11.7"
+  - "12.0"
+  - "11.14"
   - "10.15"
   - "9.11"
   - "8.15"
   - "7.10"
-  - "6.16"
+  - "6.17"
   - "5.12"
   - "4.9"
   - "iojs-v3.3"
@@ -37,6 +38,20 @@ matrix:
       env: PRETEST=true
     - node_js: "lts/*"
       env: POSTTEST=true
+    - node_js: "11.13"
+      env: TEST=true ALLOW_FAILURE=true
+    - node_js: "11.12"
+      env: TEST=true ALLOW_FAILURE=true
+    - node_js: "11.11"
+      env: TEST=true ALLOW_FAILURE=true
+    - node_js: "11.10"
+      env: TEST=true ALLOW_FAILURE=true
+    - node_js: "11.9"
+      env: TEST=true ALLOW_FAILURE=true
+    - node_js: "11.8"
+      env: TEST=true ALLOW_FAILURE=true
+    - node_js: "11.7"
+      env: TEST=true ALLOW_FAILURE=true
     - node_js: "11.6"
       env: TEST=true ALLOW_FAILURE=true
     - node_js: "11.5"
@@ -153,6 +168,8 @@ matrix:
       env: TEST=true ALLOW_FAILURE=true
     - node_js: "7.0"
       env: TEST=true ALLOW_FAILURE=true
+    - node_js: "6.16"
+      env: TEST=true ALLOW_FAILURE=true
     - node_js: "6.15"
       env: TEST=true ALLOW_FAILURE=true
     - node_js: "6.14"