Begin development of 3.1.0.0
[#60360186] Builds a better combined alpine release package

 - alpine install structure mirrors chorus install (alpine-current, alpine-releases)
 - ADR resides in shared
 - only rewrite chorus.properties if :fresh_install
 - use alpine self extracting install in vendor/alpine rather than wget-ing it
 - migrate from a 3.0.1.0 or previous combined install