Fix for issue with the way CKEditor image and widget plugins send long config data to the config form

Previously this was achieved through the URL, however this would break request limits when that data got to long or complex. Instead, we now send a POST request with the data to the server first, which stores it in the ColdBox Flash Ram. Then we send the user to the config form, at which point the stored data is picked up from Flash RAM and removed from the Flash RAM

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Flash RAM ajax helper to temporarily store complex data for iframe config dialogs

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Adding a direct helper function for renderering any old content with any specified renderer

i.e. can now do: #renderContent( data=myContent, renderer=someRegisteredRenderer )#

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Ensuring image caption is rendered as rich editor content in our richeditor image renderer

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