Merge pull request #5 from EnzoMartin78/master

Align to API structure plus general cleanup
refactor 1
refactor, support, tests
billing tests
products, expect
gettickets
cleaning
endpoint injection, billing, tests
custom api endpoints
readme
readme
readme
readme
getinvoices
Merge remote-tracking branch 'github/master'

Conflicts:
	lib/utils.js
	modules/customers.js
	package.json