Merge branch 'dev-mysql5-schemas'

Includes fixes for mysql5 to stop treating schemas as databases, and instead
merge all schemas together. If the --useschemaprefix flag is given, DBSteward
will instead prefix object names with the name of the schema they are defined
in.
Teach pgsql8 to recognise the "char" type when escaping/quoting data values
Throw an exception if there are duplicate index names defined in a single table
Create pgsql8 ExtractionTest for testing issues with pgsql8 extraction
Do pgsql8 queries via the -c flag instead of stdin
Clean up ExtractionTest logic and improve debuggability
Teach pgsql8 to extract index dimensions regardless of whether they are columns or expressions
Need to quote schema name in pgsql8 extraction to make it case-sensitive
Verify that index dimensions are being extracted in the correct order
Teach pgsql8 how to extract compound constraints
Merge branch 'dev-pgsql8-extract-constraint'

Fixes issue where pgsql8 doesn't extract compound constraints correctly.
Create unit test to verify that table and column comments are correctly extracted
Teach pgsql8 how to extract table and column comments
Merge branch 'dev-pgsql8-extract-comments'

This introduces logic to correctly extract table and column comments from
a PgSQL database.
Add unit test for mysql5 to ensure case changes result in a rename
When diffing mysql5 columns or with quoted column names, consider a change in column name case to be a rename
Add unit test to ensure pgsql8 column name case changes are handled correctly
In pgsql8, do nothing when renaming without quoting, do a rename when quoting, throw when renaming without an oldColumnName
Merge branch 'dev-column-case-change'

This addresses issues regarding case changes in column names between database
versions. In MySQL, DBSteward now considers *any* change in case to be a
renamed column. In PgSQL, following the SQL standard, case is only considered
when column quoting is turned on. In either case, if DBSteward detects a
column name case change and it would consider it a rename, but there is no
oldColumnName that explicitly marks it as such, DBSteward will error out.
Postgres 8.4 can't handle ORDER BY within array_agg(); alter query to order column names without using that