Multiple schema based multi-tenant

This way is possible to use this:

	<bean id="liquibase" class="liquibase.integration.spring.MultiTenantSpringLiquibase" depends-on="someResourceWithTheListOfSchemas">
	    <property name="dataSource" ref="dataSource"/>
	    <property name="changeLog" value="classpath:database-changelog.json"/>        
	    <property name="schemas" value="#{someResourceWithTheListOfSchemas.list}" />	    
	</bean>
	
If accepted I will take a further look in the rest of the code, including tests before proposing a new pull request.
Fixing NPE in the ChangeLogSyncVisitor when no listener is given at the time of construction. Unit tests created to test problem and verify solution.
CORE-1906 Diff between objects in different named default schemas doesn't see them as the same object
CORE-1899 Non-existing referenced sql files doesn't report error
CORE-1853 Liquibase generates invalid SQL for "character varying" type
CORE-1843 includeAll does not alphabetize classpath loaded files.

Implemented as part of changes to parser logic. Added test to ensure working correctly
Expose sax parser as a protected field for further configuration if needed such as changing validation settings
CORE-1834 generateChangeLog creates DOUBLE(22) instead of double in MySql
CORE-1831 CREATE/DROP INDEX issue: Sybase ASE 15.7.0
CORE-1797 Autoincrement on type Serial8 fails
CORE-1743 Snapshot VARCHAR(MAX) correctly on sqlserver
CORE-1727 Drop default constraint syntax for DB2 not correct
CORE-1673 Empty default value is not recorded for MySQL
Treat LoadDataChange as volitile to avoid reading potentially large csv file multiple times. Better validation for missing file
Converted FormattedSqlChangeLogParserTest to spock test
CORE-1097 Liquibase adds a semicolon after a stored proc definition making the stored proc unusable

Created test, seems to be working
Updated test based on new functionality
Wrong exception type caught
CORE-1901 DropPrimaryKey - Fails in Postgres

Updated function to support schemas
CORE-1859 DataTypeFactory doesn't take database into account