Major infrastructure changes, part 2.

* Moved helpers, common and triggers dirs into xbps-src, where
  they belong.
* Renamed the templates dir to srcpkgs, it was so redundant before.
* Make it possible to add subpkgs with no restriction in names, for
  example udev now has a subpkgs called "libgudev". Previously
  subpkgs were named "${sourcepkg}-${pkgname}".
* xbps-src: changed to look for template files in current directory.
  That means that most arguments from the targets have been removed.
* xbps-src: added a reinstall target, to remove + install.
* xbps-src: do not overwrite binpkgs by default, skip them.

And more that I forgot because it's a mega-commit that I've been
working for some days already...

--HG--
extra : convert_revision : 0f466878584d1e6895d2a234f07ea1b2d1e61b3e

xbps-src/shutils/fetch_funcs.sh

@@ -44,10 +44,10 @@ verify_sha256_cksum()
 
 fetch_update_cksum()
 {
-	local tmpl="$XBPS_TEMPLATESDIR/$pkgname/template"
 	local upcmd=$(basename $XBPS_SRCDISTDIR/$1)
 
-	sed -i -e "s|checksum.*|checksum=$(${XBPS_DIGEST_CMD} ${upcmd})|" $tmpl
+	sed -i -e "s|checksum.*|checksum=$(${XBPS_DIGEST_CMD} ${upcmd})|" \
+		template
 	return $?
 }