xbps-uhelper: new targets: binpkgarch and binpkgver.
xbps-uhelper: new targets: binpkgarch and binpkgver.

- binpkgarch: returns the architecture component of a xbps filename.
- binpkgver: returns the pkgver component of a xbps filename.

stpx/xbps,ebfe/xbps,ebfe/xbps,ebfe/xbps,datenwolf/xbps,stpx/xbps,stpx/xbps,datenwolf/xbps,datenwolf/xbps