Move Github Webhook to external plugin

See: https://github.com/kanboard/plugin-github-webhook

app/Locale/th_TH/translations.php

@@ -437,12 +437,6 @@ return array(
     // '%s changed the assignee of the task %s to %s' => '',
     'New password for the user "%s"' => 'รหัสผ่านใหม่สำหรับผู้ใช้ "%s"',
     'Choose an event' => 'เลือกเหตุการณ์',
-    // 'Github commit received' => '',
-    // 'Github issue opened' => '',
-    // 'Github issue closed' => '',
-    // 'Github issue reopened' => '',
-    // 'Github issue assignee change' => '',
-    // 'Github issue label change' => '',
     // 'Create a task from an external provider' => '',
     // 'Change the assignee based on an external username' => '',
     // 'Change the category based on an external label' => '',
@@ -487,10 +481,7 @@ return array(
     'Everybody have access to this project.' => 'ทุกคนสามารถเข้าถึงโปรเจคนี้',
     // 'Webhooks' => '',
     // 'API' => '',
-    // 'Github webhooks' => '',
-    // 'Help on Github webhooks' => '',
     // 'Create a comment from an external provider' => '',
-    // 'Github issue comment created' => '',
     'Project management' => 'การจัดการโปรเจค',
     'My projects' => 'โปรเจคของฉัน',
     'Columns' => 'คอลัมน์',
@@ -508,7 +499,6 @@ return array(
     'User repartition for "%s"' => 'การแบ่งงานของผู้ใช้ "%s"',
     'Clone this project' => 'เลียนแบบโปรเจคนี้',
     'Column removed successfully.' => 'ลบคอลัมน์สำเร็จ',
-    // 'Github Issue' => '',
     'Not enough data to show the graph.' => 'ไม่มีข้อมูลแสดงเป็นกราฟ',
     'Previous' => 'ก่อนหน้า',
     'The id must be an integer' => 'ไอดีต้องเป็นตัวเลขจำนวนเต็ม',
@@ -763,8 +753,6 @@ return array(
     // 'By @%s on Bitbucket' => '',
     // 'Bitbucket Issue' => '',
     // 'Commit made by @%s on Bitbucket' => '',
-    // 'Commit made by @%s on Github' => '',
-    // 'By @%s on Github' => '',
     // 'Commit made by @%s on Gitlab' => '',
     // 'Add a comment log when moving the task between columns' => '',
     // 'Move the task to another column when the category is changed' => '',