swift: remove unused file

Change-Id: Ibcca39d5f426203257ca4d0ed5611c5dbb838a30
swift: set memcache_serialization_support to 1

Switch new memcache entries to json but be compatible with already
written Python pickle data. This should be changed to 2 in a subsequent
commit.

Quoting release notes:
 To avoid issues on upgrades (unability to read pickled values, and cache
 poisoning for old servers not understanding JSON), we add a
 memcache_serialization_support configuration option, with the following
 values:

  0 = older, insecure pickle serialization
  1 = json serialization but pickles can still be read (still insecure)
  2 = json serialization only (secure and the default)

 To avoid an instant full cache flush, existing installations should
 upgrade with 0, then set to 1 and reload, then after some time (24
 hours) set to 2 and reload. Support for 0 and 1 will be removed in
 future versions.

Change-Id: I49cbcc5d58f0121d8b60b69f05c8e3cd5e096b36