stream_filter/httplive.c: HTTP Live Streaming

Support HTTP Live Streaming as described in the IETF draft standard:
 * http://tools.ietf.org/html/draft-pantos-http-live-streaming-04#page-8
and Apple its description:
 * http://developer.apple.com/library/ios/#documentation/networkinginternet/conceptual/streamingmediaguide/Introduction/Introduction.html#//apple_ref/doc/uid/TP40008332-CH1-DontLinkElementID_29

Not implemented (yet):
- Encrypted streams (EXT-X-KEY)
- playlist reloading for live streams

modules/stream_filter/Modules.am

 SOURCES_decomp = decomp.c
 SOURCES_stream_filter_record = record.c
+SOURCES_stream_filter_httplive = httplive.c
 
 libvlc_LTLIBRARIES += \
    libstream_filter_record_plugin.la \
+   libstream_filter_httplive_plugin.la \
    $(NULL)
 if !HAVE_WIN32
 if !HAVE_WINCE