feat(rule): update textlint-rule-ja-no-mixed-period@2.0.0 (#21)

* feat(rule): update textlint-rule-ja-no-mixed-period@2.0.0

* fix tests

Author: azu

example/package.json

@@ -1,7 +1,6 @@
 {
   "private": true,
   "scripts": {
-    "pretest": "npm rm textlint-rule-preset-ja-technical-writing && npm i",
     "textlint": "textlint ../README.md",
     "test": "npm run textlint"
   },

package.json

@@ -31,11 +31,11 @@
   ],
   "devDependencies": {
     "markdown-toc": "^1.0.2",
-    "mocha": "^3.0.0"
+    "mocha": "^4.0.1"
   },
   "dependencies": {
     "textlint-rule-ja-no-abusage": "^1.1.1",
-    "textlint-rule-ja-no-mixed-period": "^1.0.2",
+    "textlint-rule-ja-no-mixed-period": "^2.0.0",
     "textlint-rule-ja-no-successive-word": "^1.0.1",
     "textlint-rule-ja-no-weak-phrase": "^1.0.2",
     "textlint-rule-max-comma": "^1.0.2",