Remove the mandatory "per-dust-output" fee rule.

Instead, enforce a rule similar to Bitcoin:  Completely disallow (no
matter what fee) outputs less than 0.001 NMC.
Merge pull request #201 from domob1812/txfees

Remove the mandatory "per-dust-output" fee rule.
Merge pull request #205 from domob1812/enforced-fee

Enforce locked name coin amount.