change preferred name for nlist to hash, dict, ...

[loomis]

Change the preferred name for an nlist to hash, dict, or something similar. This makes is correspond better to similar data structures in other languages and is easier to understand. The generated XML and other formats should still use 'nlist' as the name of the structure.

[jrha]

+1 for dict

[loomis]

The result of the vote at the Quattor Workshop was for 'dict'. An alias for nlist needs to be added. Examples and documentation should indicate that nlist is deprecated and use dict instead.

The output formats should continue to use 'nlist'.