added updated help files for pdinfo, classinfo, and canvasinfo (by Jonathan Wilkes), merged patch by Jonathan Wilkes for the search-plugin.tcl with additional enhancements for tab/focus.

added preset_node_array abstraction and supporting help files (plus improvements to preset_node and preset_hub)

added ability for preset_hub to write/read presets or entire scenes from files. Improved documentation to reflect new additions and to improve existing.

added Jonathan Wilkes' canvasinfo and pdinfo externals (see http://osdir.com/ml/multimedia.puredata.devel/2007-10/msg00136.html)

rewrote set component of preset_node to allow for empty [set< message, adjusted and expanded documentation

reworked how default hub and node now are given context via null global symbol s_ to make things more streamlined.