Revert "[maven-release-plugin] prepare release v0.8.0-incubating"

This reverts commit 53f24b56c017ed678d5237561f4bc90209cdbde8.
[maven-release-plugin] prepare release v0.8.0-incubating
[maven-release-plugin] prepare for next development iteration
Revert "[maven-release-plugin] prepare for next development iteration"

This reverts commit 413713297a66ed9f963b6cb85c343bc16feb7b04.
Revert "[maven-release-plugin] prepare release v0.8.0-incubating"

This reverts commit 98c78663c959633e4daaad159466451a85c3f890.
Hard code scala version in pom files.

Unfortunately, having an expression inside of an artifactId causes warnings from Maven.
[maven-release-plugin] prepare release v0.8.0-incubating
[maven-release-plugin] prepare for next development iteration