[#2238] Code generation runs extremely slow for large schemas
(Inefficient DefaultRelations.getUniqueKeys() and getForeignKeys()
methods)
[#2238] Added a large H2 test schema
[#2239] Code generation runs extremely slow for large schemas
(Inefficient AbstractDatabase.filterSchema() methods)

Conflicts:
	jOOQ-meta/src/main/java/org/jooq/util/AbstractDatabase.java
[#2238] Code generation runs extremely slow for large schemas
(Inefficient DefaultRelations.getUniqueKeys() and getForeignKeys()
methods)

Conflicts:
	jOOQ-meta/src/main/java/org/jooq/util/DefaultRelations.java