Removed obsolete file copyright_config.
Now using wxAboutDialog again, instead of custom AboutDialog.
Various associated changes made.
Changed project-wide copyright years from "2013" to "2013, 2014".
Revert "Got rid of "-working-" suffix from names of built package files in CMakeLists.txt,"
This reverts commit 99c5deef787e22ee6cee4e998bfc2c6ea95a94bb.
(Reinstating "-working-" suffix.)
Removed reference to obsolete script "build_user_guide.tcl" from CMakeLists.txt.
Edited "make package" instructions in CMakeLists.txt to make more robust.