Update dependencies to enable Greenkeeper 🌴 (#20)

package.json

@@ -15,7 +15,7 @@
     "pkg-config": "~1.1.1",
     "remark": "~10.0.1",
     "remark-collapse": "~0.1.2",
-    "remark-git-contributors": "~0.3.0",
+    "remark-git-contributors": "~1.1.0",
     "remark-github": "~7.0.3",
     "remark-lint": "~6.0.2",
     "remark-lint-blockquote-indentation": "~1.0.2",
@@ -34,26 +34,31 @@
     "remark-lint-no-heading-content-indent": "~1.0.2",
     "remark-lint-no-inline-padding": "~1.0.2",
     "remark-lint-no-literal-urls": "~1.0.2",
-    "remark-lint-no-undefined-references": "~1.0.2",
+    "remark-lint-no-undefined-references": "~1.1.0",
     "remark-lint-no-unused-definitions": "~1.0.2",
     "remark-lint-table-cell-padding": "~1.0.2",
     "remark-lint-table-pipes": "~1.0.2",
     "remark-toc": "~5.1.1",
-    "remark-validate-links": "~7.1.2",
+    "remark-validate-links": "~8.0.2",
     "subarg": "~1.0.0",
-    "supports-color": "~5.5.0",
-    "unified-engine": "~6.0.1"
+    "supports-color": "~6.1.0",
+    "unified-engine": "~7.0.0"
   },
   "devDependencies": {
-    "standard": "~12.0.1",
-    "tape": "~4.9.1",
-    "vfile-reporter-json": "~1.0.2"
+    "standard": "^12.0.1",
+    "tape": "^4.10.2",
+    "vfile-reporter-json": "^2.0.0"
   },
   "repository": {
     "type": "git",
     "url": "https://github.com/vweevers/hallmark.git"
   },
   "homepage": "https://github.com/vweevers/hallmark",
+  "greenkeeper": {
+    "ignore": [
+      "supports-color"
+    ]
+  },
   "keywords": [
     "markdown",
     "documentation",