Added ability to update or remove plugins

[elcomtik]

This solves https://github.com/cloudalchemy/ansible-grafana/issues/215

It removes unwanted plugins and install&update to latest(which is default of underlaying module).

If we wanted to specify module version and don't update by default, we would need to make breaking changes to grafana_plugins variable, which I didn't wanted to make.

[elcomtik]

I looked at test, they don't test plugin installation, only verify syntax of tasks. It would be nice to modify test in such way they do not skip these tasks.

[elcomtik]

https://github.com/cloudalchemy/ansible-grafana/blob/master/molecule/alternative/tests/test_alternative.py#L15

i'm sorry, i overlooked it

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This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[elcomtik]

I had very little spare time for this task recently. However, I still have it on my personal todo list.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[elcomtik]

Still planning to work on this issue.

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[elcomtik]

Planning to work on it during hacktoberfest

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.

[elcomtik]

Still planning to work on this issue, recently had no spare time for it

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.