Add TODO for JSONRPC replacement
Narrow exceptions thrown and let them propagate up so we know
workspace file isn't valid - first step for #528
Add Javadoc.  No code changes.
Save all modified projects before importing new one - hopefully helps
#528
Comments only. No code changes.
More project saving changes for #528
- reduce project retention in memory from 1 hr to 15 min.
- free all unmodified projects if we get an error on save (we could be
running low on memory)
- make sure exceptions propagate up to where they can be usefully
handled