It's a number whichb must be ever increasing with each build submitted to the
store.
Automate its value by using the number of seconds since 1st of January 2019.
That should be enough for ~680 years.
Set them to the next release versions. In additon, the buildNumber variable will
be used to match the requirements of versionCode:
https://developer.android.com/studio/publish/versioning
that is, a monotonically increasing number, independent of the app / sdk
version.
As a step toward merging jitsi-meet-react with jitsi-meet to share as
much source code as possible between mobile and Web, merge the part of
jitsi-meet-react's source tree which supports mobile inside the
jitsi-meet source tree and leave jitsi-meet-react's Web support in the
source code revision history but don't have it in master anymore because
it's different from jitsi-meet's Web support. In other words, the two
projects are mechanically merged at the file level and don't really
share source code between mobile and Web.
