add new plugin and element

add new plugin and element

Original commit message from CVS:
* configure.ac:
* docs/plugins/gst-plugins-base-plugins-docs.sgml:
* docs/plugins/gst-plugins-base-plugins-sections.txt:
* gst/audioscale/gstaudioscale.c: (gst_audioscale_method_get_type):
* gst/audiotestsrc/Makefile.am:
* gst/audiotestsrc/gstaudiotestsrc.c:
(gst_audiostestsrc_wave_get_type), (gst_audiotestsrc_base_init),
(gst_audiotestsrc_class_init), (gst_audiotestsrc_init),
(gst_audiotestsrc_src_fixate), (gst_audiotestsrc_setcaps),
(gst_audiotestsrc_get_query_types), (gst_audiotestsrc_src_query),
(gst_audiotestsrc_wait), (gst_audiotestsrc_unlock),
(gst_audiotestsrc_create_sine), (gst_audiotestsrc_create_square),
(gst_audiotestsrc_create_saw), (gst_audiotestsrc_create_triangle),
(gst_audiotestsrc_create_silence),
(gst_audiotestsrc_create_white_noise),
(gst_audiotestsrc_change_wave), (gst_audiotestsrc_create),
(gst_audiotestsrc_set_property), (gst_audiotestsrc_get_property),
(gst_audiotestsrc_start), (plugin_init):
* gst/audiotestsrc/gstaudiotestsrc.h:
add new plugin and element
* gst/sine/gstsinesrc.c: (gst_sinesrc_class_init):
use gobject_class