pgsql: Use the term "radix tree" instead of "suffix tree" for SP-GiST t

Use the term "radix tree" instead of "suffix tree" for SP-GiST text opclass.

What we have implemented is a radix tree (or a radix trie or a patricia
trie), but the docs and code comments incorrectly called it a "suffix tree".

Alexander Korotkov

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/cb953d8b1bf7386ff20300cd80b29b7e8657dcbd

Modified Files
--------------
doc/src/sgml/indices.sgml                  |    2 +-
doc/src/sgml/spgist.sgml                   |   10 +-
src/backend/access/spgist/README           |   14 +-
src/backend/access/spgist/spgtextproc.c    |    4 +-
src/include/catalog/pg_proc.h              |   10 +-
src/test/regress/expected/create_index.out |  218 ++++++++++++++--------------
src/test/regress/expected/sanity_check.out |    2 +-
src/test/regress/output/misc.source        |    2 +-
src/test/regress/sql/create_index.sql      |  140 +++++++++---------
9 files changed, 201 insertions(+), 201 deletions(-)