replace 'semver' placeholder in release defs with git derived vsn
add include-erts cmd line arg, same as the config variable
Merge pull request #202 from tsloughter/include_erts_cli

add include-erts cmd line arg, same as the config variable
Merge pull request #201 from tsloughter/semver

replace 'semver' placeholder in release defs with git derived vsn