Add ProcessMaker to the matrix

[serenaraymond]

I think ProcessMaker should be added to this matrix: https://www.processmaker.com/. They're launching a new version on May 16, too.

[dialogik]

Thanks for your contribution. Could you please add the ProjectMaker data as a PR?

[moritzhesse]

I can see that you're not able to hand in a Pull Request and I fully understand that. Could you please help instead by filling out the "New application" template?

Name:
Version: (Application Version)
URL: (Full URL)
Creator: (Company/Author)

Platform/OS

Platform/OS: (Describe supported OSs)
Cross-Platform: yes/no
Windows: yes/no
Mac: yes/no
Linux: yes/no
Unix: yes/no

Versions/Releases

BPMN Version:
First Release: (Date)
Latest Release: (Date)

Licensing

License free: yes/no
Proprietary: yes/no
Shareware: yes/no
Open Source: yes/no