Add tag/commit to epicardium splash screen

So people can keep track and documentation can refer to it

Alternatively, we can make Epicardium version available in MicroPython as os.version using an API call like epic_get_version()

added 3-Epicardium label

assigned to @ch3

created merge request !155 (closed) to address this issue

mentioned in merge request !155 (closed)

mentioned in merge request !156 (merged)

closed via merge request !156 (merged)