Multi-Currency

Added support for multi-currency orgs and auto-conversion for currency
type destination fields
Changed test cases to support a more commonly available account field,
NumberOfEmployees
Updated Multi-Currency

Can now add classes to orgs that don't support multi-currency. Improved
detection for multi-currency.
Revert "Updated Multi-Currency"

This reverts commit 60194452d3df6f7a7e24eeb3f279a363c661b4b5.
Updated Multi-Currency

Classes can now be added to non-multi-currency orgs. Improved detection
for multi-currency.
Fix re-use of currency lookup
Merge pull request #7 from aheber/master

Thanks @ahever and @afawcett !