It seems to be a bug in EOSchemaSynchronization that substitutes the
string "add" in a statement "alter table some_table add some_column
some_type" with the string "null", resulting in a wrong SQL statement
like "alter table some_table null some_column some_type".

So I modified the code to circumvent this bug. I know it is very ugly,
but the modification is as effective as I was able to test it. I also
modified some code that was reported as deprecated.