Fixed variable scope in src_unpack()
Fixed source doc for pkgbox_package_version_parts()
Moved declaration of package default actions into separate function
Added support for SCM Subversion

Examples:
  SCM_URI="http://svn.apache.org/repos/asf/subversion/"
  pkgVer trunk
  pkgVer trunk@1295006
  pkgVer tags/1.7.8
  pkgVer branches/1.7.x