FIX: pipeline didnt trap connection error correctly
Merge pull request #50 from happybits/unstable-connect-error

FIX: pipeline didnt trap connection error correctly
make eval work with pipeline
Merge pull request #49 from happybits/unstable-eval

make eval work with pipeline
Add landscape badge
Register all nodes_callbacks and result_callbacks in pipeline object.
Add all commands from NODES_CALLBACKS as blocked commands when using pipelines