The CKEditor will be officially released in v2.1.0 due out shortly. It was included within the documentation application in v2.0.1 but the build feature was disabled and it was not included in the load all plugins" script. Therefore you should not be using this plugin until v2.1.0.
Customizing the toolbar will be done by including the the toolbar or toolbarGroups config attribute in the plugin attribute setting "CKEditor Config" e.g.
http://docs.ckeditor.com/#!/api/CKEDITOR.config-cfg-toolbar
http://docs.ckeditor.com/#!/api/CKEDITOR.config-cfg-toolbarGroups
"toolbar": /**/[{
name: "document",
groups: ["mode"],
items: ["Source"]
}, {
name: "clipboard",
groups: ["clipboard", "undo"],
items: ["Cut", "Copy", "Paste", "PasteText", "PasteFromWord", "-", "Undo", "Redo"]
}, {
name: "paragraph",
groups: ["list", "indent", "blocks", "align", "bidi"],
items: ["NumberedList", "BulletedList", "-", "Outdent", "Indent", "-", "JustifyLeft", "JustifyCenter", "JustifyRight", "JustifyBlock"]
}]/**/
By including this config you will override the Basic/Full CkEditor toolbar plugin attribute setting and customize the toolbar to your liking.
Note: the required PLJSON escaping above /**/JSON config/**/