- 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.
- Eliminated stored arg_overrides and file_override in Context.
- Removed Filter, Subst, Task, Sequence from Context.
- Remove shadow file support. Hallelujah.
- Disabled/commented out most commands, ready for the big transition
to the new parsing style.
- Obsoleted Subst.{h,cpp}.
- Obsoleted Command::exectute 'commandLine' argument. It is worse
than unnecessary, it is an uncategorized raw argument string, which
is only really useful for the 'execute' command, which itself now
calls Arguments::combine to reconstruct the command line string.
