Performance improvemnts.

- breath first search to remove larger chunks.
- shrink command list by copying to a new list.
Removed sort default hack.

The hack to compute the default value for numeric sorts did not really solve the
problem when producing an array.  The problem has been solved in the array
solver.  Hence, this hack is obsolete and was removed with this commit.
Merge branch 'master' into array
Sysdesc 2014.