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

srcpkgs/lvm2/files/lvm2.initramfs-hook

@@ -0,0 +1,33 @@
+#!/bin/sh
+
+PREREQ=""
+
+prereqs()
+{
+	echo "$PREREQ"
+}
+
+case $1 in
+prereqs)
+	prereqs
+	exit 0
+	;;
+esac
+
+if [ ! -x /sbin/lvm.static -o ! -x /sbin/dmsetup.static ]; then
+	exit 0
+fi
+
+. /usr/share/initramfs-tools/hook-functions
+
+if [ -e /etc/lvm/lvm.conf ]; then
+	mkdir -p ${DESTDIR}/etc/lvm
+	cp /etc/lvm/lvm.conf ${DESTDIR}/etc/lvm/
+fi
+
+copy_exec /sbin/dmsetup.static /sbin/dmsetup
+copy_exec /sbin/lvm.static /sbin/lvm
+
+for x in dm_mod dm_snapshot dm_mirror; do
+	manual_add_modules ${x}
+done