Starting to add subscription and preprocessing support to the spec command.
When generating a spec, show RIDs in subscribe and preprocess.
Option to leave RIDs as RIDs.
Subscribe can be a RID or alias in spec file.
Check and create preprocess
Touch up help text and some comments.
Wrap alias load in try.
tests for twee, new more consistent form for script command
Simple spec with subscribe test.
Simple test for spec preprocess
Merge commit '7bedd9090c8676a5321884d97978b0f56c4a2ca2' into newSpecFeatures
Merge pull request #33 from tadpol/newSpecFeatures

Support 'subscribe' and 'preprocess' items on data ports for the spec command
twee example
remove done todos
Merge branch 'master' into pipelines