Add placeholder to "test" directory of nl.limesco.cserv.balance so it checks out correctly, fixing an error in bndtools.
Add check for SpeakUp external account references in an Account.
Add SimService.getActiveSimsByOwnerAccountId, a function that only returns sims whose state is ACTIVATED.
Fix invoice generation for accounts that have more than one SIM, but only one of them is active. Work-around for #67.
Fix invoice generation for newly-started SIMs.

Their monthly cost item lines would have the wrong dates for the start and end dates of the monthly cost (i.e. 29-01-2013 to 19-02-2013 instead of 01-02-2013 to 28-02-2013). This was caused by the contractStartDate being in a local time-zone instead of in UTC. Also, now we force the contract to start on the first day of the next month, just like SpeakUp does.
Let the REST invoice generation use the BatchInvoicingService for pre-computing pricing of previously unpriced CDR's. This is a hack, because that code needs to move and the BatchInvoicingService needs to be removed. For now, however, it's a useful change.