configure.ac: The OpenWebRTC GStreamer plugins install no pkg-config file

And they are only a runtime dependency, no build dependency.
build: Don't use -pedantic and -ansi

They will fail the build too easily with external headers and don't do what
one would expect. Instead let autoconf figure out the right compiler flags for
using a standard conformant C compiler.
nice: Version 0.1.7.1 or newer is required to build
owr_local_media_source: Work around wrong compiler warning

owr_local_media_source.c: In function 'owr_local_media_source_get_pad':
owr_local_media_source.c:119:10: error: 'source' may be used uninitialized in this function [-Werror=maybe-uninitialized]
     if (!gst_element_link(a, b)) \
          ^
owr_local_media_source.c:296:17: note: 'source' was declared here
     GstElement *source, *capsfilter = NULL, *tee;
build: Requires gstreamer-app-1.0 and gstreamer-video-1.0 too
transport/owr_candidate: Use - instead of _ to prevent assertions with G_PARAM_STATIC_STRINGS
build: Fix linking of the bridge daemon
Require GStreamer >= 1.4 and write the version only once
Allow building with non-static GStreamer plugins
More workaround for a non-static build
build: One more nonstatic build fix

Enables loading of libopenwebrtc.so when the Owr typelib is dynamically
loaded.
WIP bridge: Move Owr init to the JavaScript side

This is needed for the js code to access the pipeline because it appears
that Seed creates its own main context (the global pipeline is stored
against the main context).