CRM-16632 Cannot save contributions with certain fee amounts

The processing of fee amounts is done inconsistently in the backend.
There are two issues:
1. in the contribution form, the "net amount" is auto-populated incorrectly when the total amount decimal value ends in 0 (e.g. $1.00, $1.10)
2. Upon saving, the CRM_Utils_Rule::cleanMoney wrapper is not used everywhere, hence the validation net_amount + fee = total amount fails when the total amount ends in a 0.

To replicate, do this (bug confirmed on Wordpress 4.6.3 demo site):

• go to create contribution page, fill out contact field with any contact name and contribution type.
• Under total amount, type "158.10" or any amount that ends with a in the decimal.
• scroll down, and under additional details, enter "8.83" for the Fee amount
• CiviCRM will automatically fill in "149.26999999999998" under the Net amount
• try saving, it will complain about the format of the net amount.
• Correct net amount to "149.27", save. CiviCRM will refuse to save saying that net amount + fee amount needs to be equal to the total amount