Обсуждение: pgsql: Move more bgworker code to bgworker.c; also, some renaming.

Move more bgworker code to bgworker.c; also, some renaming.

Per discussion on pgsql-hackers.

Michael Paquier, slightly modified by me.  Original suggestion
from Amit Kapila.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/2dee7998f93062e2ae7fcc9048ff170e528d1724

Modified Files
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src/backend/postmaster/bgworker.c           |  219 ++++++++++++++++++++++++++
src/backend/postmaster/postmaster.c         |  223 ++-------------------------
src/include/postmaster/bgworker_internals.h |    3 +
3 files changed, 232 insertions(+), 213 deletions(-)