Fix bugs in IncbinDirective
Add tests for BINCLUDE, INCBIN and INCLUDE
Add tests to improve code coverage in IntegerValueVisitor
Add tests for whitespace in operands

Add tests for whitespace in operands in instructions and directives that
handle such whitespace manually.
Add tests for continuation characters
Add test for RS with two passes

Add a test that checks that the internal counter for the RS directive is
properly reset at the start of a pass.
Add tests for RegisterList