Update copyright year
Remove fix buffer size restrictionn of pool_extract_error_message().

Per bug #90 (pool_extract_error_message: not enough buffer space).
With upcoming 3.4, we can use StringInfo infrastructure, and can
remove the restriction easily. The API for the function has been
changed: returns palloc'd buffer space. To adopt this, some client
functions in pool_process_query.c and pool_auth.c have been changed.
Fix file descriptor leak when daemonize.

Per Coverity 1111471.
Fix memory leak.

Per Coverity 1111442.
Fix some MemoryContext related problems found during testing.

Remove debug prints and single line comments which were inherited
from exception manager development branch