Fix #839: Check pkgver after parsing APKBUILD
Created by: ollieparanoid
Depends on #440 and #853, because they fix the existing wrong pkgver
s. Reviews can be done already if someone wants to.
Also changed (made testing easier and is useful in general):
- allow to specify multiple packages to
pmbootstrap parse_apkbuild
- specifying no package will parse all packages (like kconfig_check)
- JSON output is sorted in
parse_apkbuild