gst/audioscale/gstaudioscale.c: Fix getcaps to expand and union lists. (bug #138225)

gst/audioscale/gstaudioscale.c: Fix getcaps to expand and union lists. (bug #138225)

Original commit message from CVS:
* gst/audioscale/gstaudioscale.c: (gst_audioscale_expand_value),
(gst_audioscale_getcaps): Fix getcaps to expand and union lists.
(bug #138225)
* gst/debug/Makefile.am:
* gst/debug/breakmydata.c: (gst_break_my_data_plugin_init):
* gst/debug/gstdebug.c: (plugin_init):  Merge elements into one
plugin.
* gst/debug/negotiation.c: (gst_gst_negotiation_get_type),
(gst_negotiation_base_init), (gst_negotiation_class_init),
(gst_negotiation_init), (gst_negotiation_getcaps),
(gst_negotiation_pad_link), (gst_negotiation_chain),
(gst_negotiation_set_property), (gst_negotiation_get_property),
(gst_negotiation_plugin_init):  New element to talk about random
negotiation things happening in a pipeline.