Adds a flat snapshot naming scheme to projects that doesn't need sequential snapshot versions

[carlosedp]

This PR adds a config to enable flat snapshot naming. This way, each published snapshot overwrites the previous one generating an increased minor version with the "-SNAPSHOT" suffix.

Eg. Current version is "0.4.3", publishing a snapshot will generate "0.5-SNAPSHOT" until a new minor version is published overwriting the previous "0.5-SNAPSHOT" versions.

This avoids polluting the repository with incremental commit/id versions.

To use this, the user sets override def flatSnapshot = true in the trait that extends CiReleaseModule.

[ckipp01]

So if I understand this, I'm actually in preference of the opposite being the default. When you merge in a PR I want a unique snapshot that is being produced. With what you have here every one will just override the previous one, making debugging where an issue might have come in really tricky.

[carlosedp]

I kept it false as default so it will keep current behavior if nothing is set (incremental SNAPSHOTS). If the flag is overridden as true, then it overwrites the previous SNAPSHOTS:

  def flatSnapshot: Boolean = false

  override def publishVersion: T[String] = T {
    if (flatSnapshot) {
      val isTag =
        T.ctx().env.get("GITHUB_REF").exists(_.startsWith("refs/tags"))
      val state = VcsVersion.vcsState()
      if (state.commitsSinceLastTag == 0 && isTag) {
        state.stripV(state.lastTag.get)
      } else {
        val v = if (state.lastTag.isEmpty) { Array("0", "0", "0") }
        else { state.stripV(state.lastTag.get).split('.') }
        s"${v(0)}.${(v(1).toInt) + 1}-SNAPSHOT"
      }
    } else {
      VcsVersion.vcsState().format(untaggedSuffix = "-SNAPSHOT")
    }
  }

If flatSnapshot is not clear, I can rename it to something else.

[ckipp01]

Thanks! I don't have a better name, so this is fine.

[carlosedp]

Hi @ckipp01 , can you cut a version with this PR? :)
Thanks!

[ckipp01]

Just released a 0.3.0 with this.