pgsql: Add filter capability to RecursiveCopy::copypath

Add filter capability to RecursiveCopy::copypath

This allows skipping copying certain files and subdirectories in tests.
This is useful in some circumstances such as copying a data directory;
future tests want this feature.

Also POD-ify the module.

Authors: Craig Ringer, Pallavi Sontakke
Reviewed-By: Álvaro Herrera

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/a31aaec40643e0074f30b1683953cb0b3ea27036

Modified Files
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src/test/perl/RecursiveCopy.pm | 107 ++++++++++++++++++++++++++++++++++++-----
1 file changed, 96 insertions(+), 11 deletions(-)