pgsql: Add regression tests for ispell, synonym and thesaurus

Log Message:
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Add regression tests for ispell, synonym and thesaurus dictionaries.
Rename synonym.syn.sample and thesaurs.ths.sample to
synonym_sample.syn and thesaurs_sample.ths accordingly to be able to use they
in regression test.

Ispell dictionary uses synthetic simple dictionary files.

Modified Files:
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pgsql/src/backend/tsearch:
Makefile (r1.2 -> r1.3)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/tsearch/Makefile?r1=1.2&r2=1.3)
pgsql/src/test/regress:
parallel_schedule (r1.43 -> r1.44)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/parallel_schedule?r1=1.43&r2=1.44)
serial_schedule (r1.40 -> r1.41)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/serial_schedule?r1=1.40&r2=1.41)

Added Files:
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pgsql/src/backend/tsearch:
hunspell_sample.affix (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/tsearch/hunspell_sample.affix?rev=1.1&content-type=text/x-cvsweb-markup)
ispell_sample.affix (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/tsearch/ispell_sample.affix?rev=1.1&content-type=text/x-cvsweb-markup)
ispell_sample.dict (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/tsearch/ispell_sample.dict?rev=1.1&content-type=text/x-cvsweb-markup)
synonym_sample.syn (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/tsearch/synonym_sample.syn?rev=1.1&content-type=text/x-cvsweb-markup)
thesaurus_sample.ths (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/tsearch/thesaurus_sample.ths?rev=1.1&content-type=text/x-cvsweb-markup)
pgsql/src/test/regress/expected:
tsdicts.out (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/tsdicts.out?rev=1.1&content-type=text/x-cvsweb-markup)
pgsql/src/test/regress/sql:
tsdicts.sql (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/sql/tsdicts.sql?rev=1.1&content-type=text/x-cvsweb-markup)

Removed Files:
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pgsql/src/backend/tsearch:
synonym.syn.sample
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/tsearch/synonym.syn.sample)
thesaurus.ths.sample
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/tsearch/thesaurus.ths.sample)