pgsql: Add post-creation hook for extensions, consistent with other obj

Add post-creation hook for extensions, consistent with other object types.

KaiGai Kohei

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/a432e2783bb69fb68461ed2bcc460e2876fcc68d

Modified Files
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src/backend/commands/extension.c | 4 ++++
1 files changed, 4 insertions(+), 0 deletions(-)