pgsql: Add bytea datatype to ECPG.

Add bytea datatype to ECPG.

So far ECPG programs had to treat binary data for bytea column as 'char' type.
But this meant converting from/to escaped format with PQunescapeBytea/
PQescapeBytea() and therefore forcing users to add unnecessary code and cost
for the conversion in runtime. By adding a dedicated datatype for bytea most of
this special handling is no longer needed.

Author: Matsumura-san ("Matsumura, Ryo" <matsumura(dot)ryo(at)jp(dot)fujitsu(dot)com>)

Discussion: https://postgr.es/m/flat/03040DFF97E6E54E88D3BFEE5F5480F737A141F9(at)G01JPEXMBYT04

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/050710b36964dee7e1b2bf6b5ef00041fd5d2787

Modified Files
--------------
doc/src/sgml/ecpg.sgml | 34 ++-
src/interfaces/ecpg/ecpglib/data.c | 129 +++++++++
src/interfaces/ecpg/ecpglib/descriptor.c | 26 +-
src/interfaces/ecpg/ecpglib/ecpglib_extern.h | 14 +
src/interfaces/ecpg/ecpglib/execute.c | 170 +++++++++--
src/interfaces/ecpg/ecpglib/misc.c | 7 +
src/interfaces/ecpg/ecpglib/typename.c | 2 +
src/interfaces/ecpg/include/ecpgtype.h | 5 +-
src/interfaces/ecpg/preproc/ecpg.header | 2 +
src/interfaces/ecpg/preproc/ecpg.trailer | 39 ++-
src/interfaces/ecpg/preproc/type.c | 15 +-
src/interfaces/ecpg/preproc/variable.c | 1 +
src/interfaces/ecpg/test/ecpg_schedule | 1 +
src/interfaces/ecpg/test/expected/sql-bytea.c | 316 +++++++++++++++++++++
src/interfaces/ecpg/test/expected/sql-bytea.stderr | 150 ++++++++++
src/interfaces/ecpg/test/expected/sql-bytea.stdout | 8 +
src/interfaces/ecpg/test/sql/Makefile | 4 +-
src/interfaces/ecpg/test/sql/bytea.pgc | 109 +++++++
18 files changed, 983 insertions(+), 49 deletions(-)