unstable bill module
update bill module
work on bill module
save ispaid status
bill module works independently
bills displayed in collection details page
update style bill
change is paid status directly from bill index page
Merge branch 'bill-module' into develop
fix style popup + add bill details popup
bill edit popup
popup edit bill
add bill from collection details page + clean cod
fix bugs
fix js bug + add comments in collection
Update readme file
Update readme file