[Improvement] Button: adjust padding of small button (#511)

package.json

@@ -50,7 +50,7 @@
     "vue": ">= 2.5.0"
   },
   "devDependencies": {
-    "autoprefixer": "^7.2.3",
+    "autoprefixer": "^7.2.4",
     "avoriaz": "2.0.0",
     "babel-cli": "^6.26.0",
     "babel-core": "^6.26.0",
@@ -82,10 +82,10 @@
     "karma-spec-reporter": "^0.0.32",
     "karma-webpack": "^2.0.9",
     "mocha": "^4.0.1",
-    "postcss": "^6.0.14",
+    "postcss": "^6.0.15",
     "postcss-calc": "^6.0.0",
     "postcss-easy-import": "^3.0.0",
-    "postcss-loader": "^2.0.9",
+    "postcss-loader": "^2.0.10",
     "precss": "2.0.0",
     "progress-bar-webpack-plugin": "^1.10.0",
     "rimraf": "^2.5.4",
@@ -97,9 +97,9 @@
     "url-loader": "^0.6.2",
     "vant-doc": "1.0.1",
     "vue": "^2.5.13",
-    "vue-loader": "^13.6.1",
+    "vue-loader": "^13.6.2",
     "vue-router": "^3.0.1",
-    "vue-sfc-compiler": "^0.0.6",
+    "vue-sfc-compiler": "^0.0.7",
     "vue-style-loader": "^3.0.0",
     "vue-template-compiler": "^2.5.13",
     "vue-template-es2015-compiler": "^1.6.0",