Moneyed dependency

[akolpakov]

After merging pull request #3 new dependency in file utils.py has been created:

import moneyed

A reason why modules were messed up is not clear. There was two independent modules moneyed for storing money type and djmoney_rates for money convertation.
If someone wants to use these modules together - why not, but there are no needs to inject one into another.

By pull request #3 was implemented one particular usage case of this module. This is not right and breaks module structure.

CC: @tzenderman

[tzenderman]

Your comment makes sense, but I didn't think anyone that is using this would not be using the py-moneyed package. @synasius we could remove the util function convert_money https://github.com/evonove/django-money-rates/pull/3/files#diff-cec83698a31b7e3204fb01ff85b29c16R58 and add it to the Readme as an option for the developer to implement in his own project. This would break backwards compatibility though and would probably need a full version bump though?