You can uninstall or removes an installed eclipse-mylyn-context-cdt package itself from Ubuntu 16.10 (Yakkety Yak) through the terminal,
$ sudo apt-get remove eclipse-mylyn-context-cdt
If you would like to remove eclipse-mylyn-context-cdt and it's dependent packages which are no longer needed from Ubuntu,
$ sudo apt-get remove --auto-remove eclipse-mylyn-context-cdt
If you use with purge options to eclipse-mylyn-context-cdt package all the configuration and dependent packages will be removed.
$ sudo apt-get purge eclipse-mylyn-context-cdt
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 eclipse-mylyn-context-cdt