在Sublime Text 3 MarkdownEditing插件打开md文件默认的主题很丑，而且文字居中，左侧有大片空白，需要修改配置文件调整一下。
流程:
ctrl+shift+p打开命令输入，打开Preference: MarkdownEditing Setting: User
ctrl+shift+p打开命令输入，打开Preference: MarkdownEditing Setting: Default
将Preference: MarkdownEditing Setting: Default对应文件内容复制到Preference: MarkdownEditing Setting: User中
在Preference: MarkdownEditing Setting: User中修改
"color_scheme": "Packages/MarkdownEditing/MarkdownEditor.tmTheme",
// "color_scheme": "Packages/MarkdownEditing/MarkdownEditor-Dark.tmTheme",
改为
// "color_scheme": "Packages/MarkdownEditing/MarkdownEditor.tmTheme",
"color_scheme": "Packages/MarkdownEditing/MarkdownEditor-Dark.tmTheme",
修改主题为深色，与sublime主题一一致
再修改
// Layout
"draw_centered": false, // 改为false，原始值为true
"word_wrap": true,
"wrap_width": 120, // 每行字符数上限
"rulers": [],
"draw_centered": false, // 改为false，原始值为true
"word_wrap": true,
"wrap_width": 120, // 每行字符数上限
"rulers": [],
配置完毕。
