uridownloader: Add API to specify the referer of a request
hlsdemux: Set Referer in requests to the playlist URI
uridownloader: Unset referer if none was specified later on
gl: fix string literal warning

warning: format not a string literal, argument types not checked [-Wformat-nonliteral]
glfilter: only warn when other_context attribute is set

Fix false positive
gl: use gst_gl_platform_from_string because we support gl shareList on all platforms
gl: append EGL_LIB to GL_LIB
gl: append GL_LIB and GL_CFLAGS in pc files
egl: remove pc files

Forgot to do that in 09116bf10d515d50bdd1e9a20278be816cb762aa:
"egl/eglglessink: remove since EGLImage and iOS support have been added in glimagesink"
gl/examples: move to -bad

- fix all the compiler errors
- give them their own gl directory
gl/examples/sdl: update for the latest gstgl changes
gl: Reduce noisy Info level output to LOG
gl/sdl example: Fix uninstalled build
h264parse: unref/replace force_key_unit_event in gst_h264_parse_reset

https://bugzilla.gnome.org/show_bug.cgi?id=729200
sndfile: send a toc for the segments in the audio file
tests: drop direct include

It is only allowed to include gdk/gdkx.h and that will bring all the x11 things.
examples: gl: add missing entry to cflags to find gst/gl/gl.h

Otherwise build fails
gl: add missing G_BEGIN/END_DECLS in utils header
hlsdemux: replace uridownloader with a GstElement

The GstElement is directly linked into a ghost pad and
its buffers are pushed as received downstream. This way the
buffers are small enough and not a whole fragment that usually
causes extra latency and makes buffering harder
hlsdemux: re-enable decryption after uridownloader removal

Now the decryption is done buffer by buffer instead of on the
whole fragment at once. As it expects multiples of 16 bytes a
GstAdapter was added to properly chunk the buffers.

Also the last buffer must be resized depending on the value of the
last byte of the fragment, so hlsdemux always keeps a pending buffer
as it doesn't know if it is the last one yet