Reduce memery taken. close #782
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Little tweaking
Add test specs for loading duplicated ids
Rebuild packages
Rebuild packages
Add resolveCache to support config changing dynamically
Remove support for changing condig dynamically
Fix a bug for top-level id
Remove module._resolveCache
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Add requested event for combo plugin to clean up memory usage
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Change data structure of comboHash object
Rebuild plugins
DO NOT tweak performance for rare case
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Delete some private object to free memory
Update test specs
Rebuild packages