Fix coding style: replace tab with whitespace in mattermost config

Signed-off-by: Chengwei Yang <yangchengwei@qiyi.com>

config/config.json

@@ -10,7 +10,7 @@
     "ServiceSettings": {
         "SiteName": "Mattermost",
         "Mode" : "dev",
-		"AllowTesting" : false,
+        "AllowTesting" : false,
         "UseSSL": false,
         "Port": "8065",
         "Version": "developer",

docker/0.6/config_docker.json

@@ -10,7 +10,7 @@
     "ServiceSettings": {
         "SiteName": "Mattermost",
         "Mode" : "dev",
-		"AllowTesting" : false,
+        "AllowTesting" : false,
         "UseSSL": false,
         "Port": "80",
         "Version": "developer",
@@ -63,8 +63,8 @@
         "SMTPUsername": "",
         "SMTPPassword": "",
         "SMTPServer": "",
-		"UseTLS": false,
-		"UseStartTLS": false,
+        "UseTLS": false,
+        "UseStartTLS": false,
         "FeedbackEmail": "",
         "FeedbackName": "",
         "ApplePushServer": "",

docker/0.7/config_docker.json

@@ -10,7 +10,7 @@
     "ServiceSettings": {
         "SiteName": "Mattermost",
         "Mode" : "dev",
-		"AllowTesting" : true,
+        "AllowTesting" : true,
         "UseSSL": false,
         "Port": "80",
         "Version": "developer",
@@ -65,8 +65,8 @@
         "SMTPUsername": "",
         "SMTPPassword": "",
         "SMTPServer": "",
-		"UseTLS": false,
-		"UseStartTLS": false,
+        "UseTLS": false,
+        "UseStartTLS": false,
         "FeedbackEmail": "",
         "FeedbackName": "",
         "ApplePushServer": "",

docker/dev/config_docker.json

@@ -10,7 +10,7 @@
     "ServiceSettings": {
         "SiteName": "Mattermost",
         "Mode" : "dev",
-		"AllowTesting" : true,
+        "AllowTesting" : true,
         "UseSSL": false,
         "Port": "80",
         "Version": "developer",
@@ -65,8 +65,8 @@
         "SMTPUsername": "",
         "SMTPPassword": "",
         "SMTPServer": "",
-		"UseTLS": false,
-		"UseStartTLS": false,
+        "UseTLS": false,
+        "UseStartTLS": false,
         "FeedbackEmail": "",
         "FeedbackName": "",
         "ApplePushServer": "",