Minor Refactoring

- Added support for more type-specific checks of attribute values.
- Added support for more type-specific attribute rendering.
- Improved generalized methods for checking columns in a report.
- Added unit tests.
- Minor code cleanup.
- Added secret hidden feature for internal testing.

src/columns/CMakeLists.txt

@@ -27,6 +27,7 @@ set (columns_SRCS Column.cpp Column.h
                   ColTags.cpp ColTags.h
                   ColUntil.cpp ColUntil.h
                   ColUrgency.cpp ColUrgency.h
+                  ColUDA.cpp ColUDA.h
                   ColUUID.cpp ColUUID.h
                   ColWait.cpp ColWait.h)