By default, Joomla is using TinyMCE in advanced mode. Even it calls "Advanced Mode", the functions are very basic, it is without any functions to control table, such as adding/deleting rows.
Acutally, TinyMCE has this kind of functions, You do not need to install any new plug-ins. Please go to Administration Panel, Click->Extensions-> Plug-ins-> Plug-in Manager: Editor - TinyMCE -> Select Functionality-> Extended.

There will be an extra row of icons in the TinyMCE.