Packaging version and file name consolidation

At a high level:
- fdbsqllayer and fdbsqllayer.cmd do a (limited) search for the jar instead of assuming a name
    - shell script is a bit more defensive, exiting instead of piping "UNKNOWN" places
- build_packages.sh and build_installer.cmd pull the version out pom, instead of duplicating, and also do a jar search
    - batch script uses powershell instead of grep for pom interaction
- All packages now have a 0/1 release indicator, as the core does. Add this to the version properties file, too.
- spec file now gets the variables for version and files to eliminate sed. Only set the Epoch (used for our internal tests systems) on non-releases.
-  deb substr doesn't (seem to) apply to changelog or links, where we need it, so use sed for version and files

All of this conspires to eliminate the version number from everywhere except `pom.xml`. This means the next release, and subsequent bump, have to change exactly 1 file.