Fix PHP notice on pull/push fields

See merge request sdoc/billrun!2935

BRCD-1824 - Keep notes for payments

See merge request sdoc/billrun!2925

BRCD-1812 - Payment agreement

See merge request sdoc/billrun!2923

BRCD-1807: Credit lines installments support

See merge request sdoc/billrun!2920

# Conflicts:
#	application/controllers/Action/Pay.php
#	library/Billrun/Bill/Payment.php

rearrange code. 

BRCD-1805 - New payment method "Deposit"

See merge request sdoc/billrun!2907

BRCD-1807: when checking for future billruns - make sure it is a 6 digits billrun only (no one time)

BRCD-1807: when checking for future billruns - make sure it is a 6 digits billrun only (no one time)

BRCD-1807: handle future installments (on account or subscriber level) in case of subscriber termination

API b/c to ver. 3 (BRCD-1798)

See merge request sdoc/billrun!2893

BRCD-1803 fix(BillAPI - Move) - PHP Notice:  Undefined index: _id

Closes BRCD-1803

See merge request sdoc/billrun!2908

BRCD-1804 - cant update unit time of "Custom Period service".

See merge request sdoc/billrun!2906

fix PHP Notice about using static porerty as non static

See merge request sdoc/billrun!2910

Restore some js/css + favicon

See merge request sdoc/billrun!2911