CFY-872 modified keypair configuration for bootstrap - removed 'provided' option
CFY-872 flake8 fix
CFY-872 added validation for keypair configuration. also, an existing keypair file will now never be overwritten.
CFY-872 fixed openstack provider schema
CFY-872 fixed openstack provider schema
CFY-872 fixed messages
CFY-872 fixed bug from previous commit
Merge pull request #26 from cloudify-cosmo/feature/CFY-872-modify-keypair-configuration-for-bootstrap

Feature/cfy 872 modify keypair configuration for bootstrap