Add length-based fee for name_update.

Change the name_update fee to include 0.002 HUC per 100 characters of
length in addition to the minimum fee of 0.01 HUC.
Add length-based fee for name_update.

Change the name_update fee to include 0.002 HUC per 100 characters of
length in addition to the minimum fee of 0.01 HUC.
Merge branch 'update-fees' of github.com:domob1812/huntercoin into update-fees
Merge pull request #33 from domob1812/update-fees

Add length-based fee for name_update.