Update directory structure related to prepare module.
- Previously, automation scripts related to prepare module were stored
under the Scripts/Modules/Prepare directory and their related
documentation files at Documentation directory. This organization
seems to be inappropriate when building rpm packages. In order to
provide a better organization, this update automation scripts
related to prepare module from Scripts/Modules/Prepare directory to
tcar-scripts-prepare directory and the related documentation files
from Documentation to tcar-scripts-prepare-docs directory.