pgsql: Move pg_lzcompress.c to src/common.

Move pg_lzcompress.c to src/common.

Exposing compression and decompression APIs of pglz makes possible its
use by extensions and contrib modules. pglz_decompress contained a call
to elog to emit an error message in case of corrupted data. This function
is changed to return a status code to let its callers return an error instead.

This commit is required for upcoming WAL compression feature so that
the WAL reader facility can decompress the WAL data by using pglz_decompress.

Michael Paquier

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/60838df922345b26a616e49ac9fab808a35d1f85

Modified Files
--------------
src/backend/access/heap/tuptoaster.c  |   11 +-
src/backend/utils/adt/Makefile        |    4 +-
src/backend/utils/adt/pg_lzcompress.c |  779 --------------------------------
src/common/Makefile                   |    3 +-
src/common/pg_lzcompress.c            |  786 +++++++++++++++++++++++++++++++++
src/include/common/pg_lzcompress.h    |  112 +++++
src/include/utils/pg_lzcompress.h     |  112 -----
src/tools/msvc/Mkvcbuild.pm           |    3 +-
8 files changed, 911 insertions(+), 899 deletions(-)