Add base classes for processor integration tests

There is no consistant definition of what tests should be covered in
processors.  Base classes for tests have been created to resolve this.

Assumptions have been made in regards to test classification.

 1. Some SQL RDMS do not have support for schemas or sequences
 2. Some SQL RDMS that support schemas, such as Oracle Database, present a
 challenge to test multiple schemas.
  * For Oracle Database, a schema is tied to the user defined in the
  connection string.
 3. Some existing tests appeared too specific and do not need a base class
Move processor tests into individual folders

Kept this commit seperate to help those who may want to rebase their work
over my changes.
Organise SQL Server integration tests

 1. Test table did not correctly quote table names
 2. Test table only supported one column - incorrect brackets
 3. No existing test coverage regarding schemas, constraints or indexes
Organise SQL Server CE integration tests

Test table did not allow custom index or constraint names. This is useful
for testing single quotes in index and constriant names.
Organise Postgres integration tests

Test table constuctor did not match existing pattern
 * "(table, processor / connection, schema, columns)"
Organise Oracle integration tests

 1. Found bug in processor code - object names were not been escaped
 properly.
 2. Test table constructor changed to match pattern (see previous commit)
Organise Firebird integration tests

Test table constructor changes to match pattern (see previous commits)
Merge pull request #406 from matthewdunsdon/RefactorProcessorTests

Refactor Processor Integration Tests