Please remove plugin data on plugin uninstall.

[wpgeek922]

Describe the bug
The wp-session-manager plugin does not remove the plugin data when uninstall. You need to clean up wp_options table when your plugin is removed from the site. We have encountered serious performance issues on the site dashboard. On debugging the issue we've found that your plugin is no more in use and it is removed from site but it has more than 800000 records in wp_options table. Slowing the admin down to 25-30 seconds load time. That's insane.

Even when the plugin is in use, you need to purge the wp_session and _wp_session_expires on a regular basis.

To Reproduce
Just check the wp_options table for "_wp_session" and "_wp_session_expire" options you will come to know the number of records it has.

Expected behaviour
A good plugin should always have garbage collection and does not leave the unused data behind in the database.

I hope you do something about it.

Thanks,
Imtiyaz