CodeSnip Old Code (SVN)

* Changed preview dialog box and IPreview interface to accept doc content as TEncodedData rather than a string.
* Changed all implementations of IPreview accordingly.
* Also updated affected using units.

Modified preview dialog box and interface not to try to extract doc title from document - caller must now provide title if needed. Updated affected units and removed any now unused code.

Development branch for CodeSnip release 4.

Initial source is a copy of v3.8.4 (r1075).