Added whereParams clause.
Allows for the injection of parameters into a where clause.
This means that database independent values can be set.
Allows for use of sequence functions as well.

Added super class to encapuslate common fields in update and delete changes.
Reverted change in TableWriter as TypeConverterFactory class does not appear to be in the source code.
Merge branch 'whereParams' of https://github.com/vorbis/liquibase into vorbis-whereParams

Conflicts:
	liquibase-core/src/main/java/liquibase/change/core/DeleteDataChange.java
	liquibase-core/src/main/java/liquibase/change/core/UpdateDataChange.java
	liquibase-core/src/main/java/liquibase/sqlgenerator/core/DeleteGenerator.java
Merge branch 'whereParams' of https://github.com/vorbis/liquibase into vorbis-whereParams

Conflicts:
	liquibase-core/src/main/java/liquibase/change/core/DeleteDataChange.java
	liquibase-core/src/main/java/liquibase/change/core/UpdateDataChange.java
	liquibase-core/src/main/java/liquibase/sqlgenerator/core/DeleteGenerator.java