You can uninstall or removes an installed mha4mysql-node package itself from Ubuntu 14.04 LTS (Trusty Tahr) through the terminal,
$ sudo apt-get remove mha4mysql-node
If you would like to remove mha4mysql-node and it's dependent packages which are no longer needed from Ubuntu,
$ sudo apt-get remove --auto-remove mha4mysql-node
If you use with purge options to mha4mysql-node package all the configuration and dependent packages will be removed.
$ sudo apt-get purge mha4mysql-node
If you use purge options along with auto remove, will be removed everything regarding the package, It's really useful when you want to reinstall again.
$ sudo apt-get purge --auto-remove mha4mysql-node