Subject: removed OSCAD.tar.gz from OSCAD_installer

Description:

1) removed OSCAD.tar.gz from OSCAD_installer/
2) instead, moved OSCAD/ to OSCAD_installer
3) changes in OSCAD_insaller/installOSCAD.sh
   - will copy OSCAD to $installDir instead of extracting
   - copy desktop icon
Merge pull request #3 from psachin/master

cleanup, see description below