[SeaBIOS] Release ratonale

[Leonardo Passos]

Dear all,

I am using Seabios for a personal project and I need to try different
versions of it.
After cloning the project code, I see many releases when issuing git tag,
but which ones are stable? Clearly, 1.7.5-rc1 isn't, but what about the
others?

Stated otherwise, what is the rationale of release numbering in Seabios?

Regards,

Leonardo.