pgsql: Modify copyright.pl so all lines are processed, not just the fir

Modify copyright.pl so all lines are processed, not just the first
match, so files that contain embedded copyrights are updated, e.g.
pgsql/help.c.

Backpatch to 9.2.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/95203e0833664a1cb221e4f3ad766d167db893b8

Modified Files
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src/tools/copyright.pl | 10 ++++------
1 files changed, 4 insertions(+), 6 deletions(-)