`ejira-update-my-projects` should be asynchronous

[LeonardMH]

`ejira-update-my-projects` should be asynchronous

[nyyManni]

Thanks for the feedback.

I fully agree that for the sake of the user experience all the update commands should be asynchronous. That was something I considered when creating the jiralib2 library but left it for the future for simplicity's sake.

I currently do not have the free time to allocate for implementing it but will happily merge a pull request if someone else is willing to spend the effort.

For the time being, in your use case it could be beneficial to create a custom update function which would filter the issues based on the last modification date (I hope all 20k of the issues have not been touched within the last few months for example?)