[ruby-cvs:71319] akr:r64227 (trunk): Store String as zone in struct vtm.

[akr at ruby-lang.org]

akr	2018-08-08 19:00:43 +0900 (Wed, 08 Aug 2018)

  New Revision: 64227

  https://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=64227

  Log:
    Store String as zone in struct vtm.
    
    This removes zone_table and use fstring instead.

  Modified files:
    trunk/strftime.c
    trunk/time.c
    trunk/timev.h