Fix Dashboard DB tab details for Postgres

[ryanrdoherty]

Broken sections include:

• Identifiers table (all lookups): need to use PG-specific queries, and some fields may not be 1:1 anyway
• Aliases: Lookup has hard-coded oracle context. This one is easier. See https://github.com/VEuPathDB/EbrcWebsiteCommon/blob/master/Site/dashboard/lib/LdapTnsNameResolver.php