hevc: Use a regular configurationVersion.

Now, 14496-15 3rd ed. was finalized and published, so it established the compatibility of the structure of the decoder configuration.
muxer: Re-enable HEVC muxing.

Remove the restriction to use for testing and experimental purposes only.
public header: Fix two typos in comments about lsmash_codec_specific_data_t.
public header: Update micro ver. because of regular HEVC support.
Define macros of endian memory reader/writer.
timeline: Fix a wrong increment to get ctd_shift.
Implementation of referencing external media files.