As the consensus in:
https://www.redhat.com/archives/libvir-list/2012-July/msg01692.html,
this patch is to destroy conf/virdomainlist.[ch], folding the
helpers into conf/domain_conf.[ch].

* src/Makefile.am:
  - Various indention fixes incidentally
  - Add macro DATATYPES_SOURCES (datatypes.[ch])
  - Link datatypes.[ch] for libvirt_lxc

* src/conf/domain_conf.c:
  - Move all the stuffs from virdomainlist.c into it
  - Use virUnrefDomain and virUnrefDomainSnapshot instead of
    virDomainFree and virDomainSnapshotFree, which are defined
    in libvirt.c, and we don't want to link to it.
  - Remove "if" before "free" the object, as virObjectUnref
    is in the list "useless_free_options".

* src/conf/domain_conf.h:
  - Move all the stuffs from virdomainlist.h into it
  - s/LIST_FILTER/LIST_DOMAINS_FILTER/

* src/libxl/libxl_driver.c:
  - s/LIST_FILTER/LIST_DOMAINS_FILTER/
  - no (include "virdomainlist.h")

* src/libxl/libxl_driver.c: Likewise

* src/lxc/lxc_driver.c: Likewise

* src/openvz/openvz_driver.c: Likewise

* src/parallels/parallels_driver.c: Likewise

* src/qemu/qemu_driver.c: Likewise

* src/test/test_driver.c: Likewise

* src/uml/uml_driver.c: Likewise

* src/vbox/vbox_tmpl.c: Likewise

* src/vmware/vmware_driver.c: Likewise

* tools/virsh-domain-monitor.c: Likewise

* tools/virsh.c: Likewise