[WIP] project billing detail
[WIP]Feature #71463. Resource Mgmt: Report: Project Billing Report
Merge branch 'dev_mirror' into billing_report
fix layout label
fix nil error
fix actual hours when biling model is man-months
Change computation for forecast hours when man-months
modify csv
Merge branch 'billing_report' into dev_mirror

Conflicts:
	app/controllers/resource_managements_controller.rb
	routes.rb