Initial implementation of the new ports API, refs #136
Allow multiple non-addressable connections with regular ports, fixes #90
Switch subgraph component to use new port API, refs #136
Support for the new simpler component API, refs #97
Test more of the new port events inside subgraph, refs #136
More port checks
Initial docs on new component and port APIs in ChangeLog
Dev version of Node.js is a dev version
Auto-export only unattached ports, refs #90
Check exporting situation first, refs #90
Events for exported ports
Support simpler component loading also for file-based components
test: Remove dead tests, using spec/ instead now
Journal: Start of implementation
Journal: Introduce an initial (null) entry
Journal: Add API for moving between revisions
Graph: Add start/endTransaction API

Will allow journal to group changes more sanely.
Journal: Implement transactions

This gives more meaningful revision numbers:
All initial state belong to revision 0,
all changes from a single API call like .removeNode (incl. iip/edge removal),
and API consumers can manually create transactions and attach metadata there.
Journal: Add undo/redo API
Journal: Use mocha for tests, move to spec/