0000513: Store amount paid on each each service

Notes
(0000640) ivan (administrator) 2009-02-20 21:47	Can this not be determined from the transactions table?

(0000644) paulh (administrator) 2009-02-21 13:49	Sorry should have put a few more words in this report ;-) This is for contracts which are not billable as bug 512 lists the list price for the product we should show the price the customer actually paid. e.g. customer is academic and purchases Linux support which has a list price of $10 though after battering with sales they pay $8 so we should store what they actually paid so when the come to renew we know if they got a special deal last year. We originally intended to use services for renews as well (rather than just editing the end date of the contract) we need to be careful here that we don't cause confusion between billing contracts and renews (if that makes sense)

(0001115) paulh (administrator) 2009-05-27 19:24	This is something that would be useful though needs to be carefully thought through. Hopefully we can use the services stuff we've started. Bumping to 3.60

(0004170) ivan (administrator) 2011-08-06 19:08	Bug 0000512 is bumped to 4.0 so this ought to be as well since it depends on it.