support for use_strict

variable appears unused but results in

ReferenceError: flowfile is not defined

when node is invoked with --use_strict
Increase double-click to edit time
Merge pull request #204 from tedgoddard/patch-1

support for use_strict - patch for server.js file
Removes redundant variable declaration.
(now handled in storage)
Patch to Support use strict
Fixes Issue #206
(manual merge due ot other changes)
Patch to suppoer use strict
Fixes Issue #205
Manual merge due to other changes
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Actually make xml2js and json2xml deprecated 
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Self inflicted type - apologies to all...
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Allow Serial nodes to close asynchonously
Add tests for async close
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