Added post-build script to copy pak and dll files, fixed PolycodeDir variable
Added post-build script to copy pak and dll files, fixed PolycodeDir variable

* Tweaked PolycodeDir variable so that it matches visual studio conventions (includes a trailing slash)

* Added post-build event script to copy default.pak and hdr.pak if they don't already exist in the solution directory

* Added post-build event script to copy the release or debug openal32 and zlib dlls to built target directory if they don't already exist

GovanifY/Polycode,Xetlin/Lua,hksonngan/Polycode,cartman300/Polycode,thorsummoner/polycode,sshaileshk/Polycode,sshaileshk/Polycode,sshaileshk/Polycode,hksonngan/Polycode,Xetlin/Lua,carlosmarti/Polycode,mcclure/backup-Polycode,zeebok/Polycode,GovanifY/Polycode,carlosmarti/Polycode,mcanthony/Polycode,cartman300/Polycode,ivansafrin/Polycode,fodinabor/Polycode,zeebok/Polycode,thorsummoner/polycode,mcanthony/Polycode,GovanifY/Polycode,mcanthony/Polycode,mcclure/backup-Polycode,mcclure/backup-Polycode,ivansafrin/Polycode,cartman300/Polycode,ivansafrin/Polycode,Xetlin/Lua,sshaileshk/Polycode,fodinabor/Polycode,fodinabor/Polycode,hksonngan/Polycode,hksonngan/Polycode,zeebok/Polycode,thorsummoner/polycode,GovanifY/Polycode,cartman300/Polycode,fodinabor/Polycode,Xetlin/Lua,ivansafrin/Polycode,thorsummoner/polycode,zeebok/Polycode,mcanthony/Polycode,carlosmarti/Polycode