Build version based only on assets in source code

[mrq1911]

Currently, version is grabbed from the last tag in the git tree, this, however, doesn't work if you don't build from git repo, or you just pulled a shallow branch.

There are multiple ways how to solve it:

• metadata in node/Cargo.toml
• parse changelog
• add a file with this information

also if the source is not built from git repo, revision hash shouldn't be present I the version string

[jak-pan]

I'd go with changelog as we already do that and everything else is more maintenance work.