CodeMirror 5.16.0 发布了，CodeMirror 是一款“Online Source Editor”，基于Javascript，短小精悍，实时在线代码高亮显示，他不是某个富文本编辑器的附属产品，他是许多大名鼎鼎的在线代码编辑器的基础库。
Bugs 修复：
Fix glitches when dragging content caused by the drop indicator receiving mouse events.
Make Control-drag work on Firefox.
Make clicking or selection-dragging at the end of a wrapped line select the right position.
show-hint addon: Prevent widget scrollbar from hiding part of the hint text.
rulers addon: Prevent rulers from forcing a horizontal editor scrollbar.
新特性：
search addon: Automatically bind search-related keys in persistent dialog.
sublime keymap: Add a multi-cursor aware smart backspace binding.
