[PEP8] in tests
lint
fix mutable default parameter
remove deprecated fast_suite and checks
bump version: module changed substantially in v8
travis: add dependency on purchase-workflow
lint
Merge remote-tracking branch 'yvaucher/8.0-logistic_requisition' into 8.0-PR_tests

Conflicts:
	logistic_requisition/tests/test_mto_workflow.py
	logistic_requisition/tests/test_sale_order_from_lr_confirm.py