Fixed

• Fixed role chaining #471 (#481)
• Fixed loading config from default section 955600c

Added

• rotate: Added the --no-session flag to use the master credentials instead of using a temporary session #478 (#481)
• Config environment var AWS_CHAINED_SESSION_TOKEN_TTL to specify the TTL for chained sessions (#481)
• exec: sets an environment variable AWS_SESSION_EXPIRATION #473
• release binaries for linux amd64 #487