/**
 * @license Copyright (c) 2003-2017, CKSource - Frederico Knabben. All rights reserved.
 * For licensing, see LICENSE.md or http://ckeditor.com/license
 */

 CKEDITOR.editorConfig = function( config ) {
	// Define changes to default configuration here.
	// For complete reference see:
	// http://docs.ckeditor.com/#!/api/CKEDITOR.config

	config.uiColor = '#F2F2F2';

	// The toolbar groups arrangement, optimized for two toolbar rows.
	config.toolbarGroups = [
		{ name: 'document',	   groups: [ 'mode', 'document', 'doctools' ] },
		//{ name: 'clipboard',   groups: [ 'clipboard', 'undo' ] },
		{ name: 'basicstyles' },
		{ name: 'links' },
		{ name: 'blocks' },
		{ name: 'insert' },
		{ name: 'align' },
		{ name: 'cleanup' },
    { name: 'codesnippet' },
    { name: 'imgur' },
		//'/',
		{ name: 'paragraph',   groups: [ 'list' ] },
		{ name: 'styles' },
		{ name: 'colors' },
		{ name: 'tools' },
		{ name: 'about' }
	];
	// Whether the toolbar can be collapsed by the user.
	//config.toolbarCanCollapse = true;
	//config.toolbarStartupExpanded = true;

	// Remove some buttons provided by the standard plugins, which are
	// not needed in the Standard(s) toolbar.
	config.removeButtons = 'PasteText,PasteFromWord,Cut,Copy,Paste,Undo,Redo,Anchor,Blockquote,HorizontalRule,Format,Font,Image,Styles,SpecialChar,Templates';

	// Set the most common block elements.
	config.format_tags = 'p;h1;h2;h3;pre';

	// Simplify the dialog windows.
	config.removeDialogTabs = 'image:advanced;link:advanced;link:upload';

	// Set the file uploader
	config.filebrowserUploadUrl = g5_editor_url+"/upload.php?type=Images";

	// Set Editor default Height
	config.height = 300;

	// CODESNIPPET SETTING
	config.extraPlugins = 'codesnippet,simpleuploads,imgur';
  config.codeSnippet_theme = 'school_book';
  config.imgurClientId = '';
	// CKEDITOR PLUGINS LOADING
	//config.extraPlugins = 'pbckcode'; // add other plugins here (comma separated)
	// PBCKCODE CUSTOMIZATION
	/*
	config.pbckcode = {
		// An optional class to your pre tag.
		cls: 'line-numbers',

		// The syntax highlighter you will use in the output view
		highlighter: 'PRISM',

		// An array of the available modes for you plugin.
		// The key corresponds to the string shown in the select tag.
		// The value correspond to the loaded file for ACE Editor.
		modes: [['HTML', 'html'], ['CSS', 'css'], ['PHP', 'php'], ['JS', 'javascript']],

		// The theme of the ACE Editor of the plugin.
		theme: 'twilight',

		// Tab indentation (in spaces)
		tab_size: '4'
	};
	*/
};

config.js 에서 제가 사용하는 방법입니다.

    config.removeButtons = 'PasteText,PasteFromWord,Cut,Copy,Paste,Undo,Redo,Anchor,Blockquote,HorizontalRule,Format,Font,Image,Styles,SpecialChar,Templates';

    // Simplify the dialog windows.
    config.removeDialogTabs = 'image:advanced;link:advanced;link:upload';

에 image 추가로 기본 ckeditor 이미지 업로드 버튼 삭제

    // CODESNIPPET SETTING
    config.extraPlugins = 'codesnippet,simpleuploads,imgur';

사용하고자 하시는 플러그인이 다수라면 위처럼 , 로 구분하여 수정해주시면 됩니다.^^