Refactoring + move compute-sanitizer to cuda-tools

This includes moving compute-sanitizer from cuda to cuda-tools and some refactoring:

• Drop integration subdirectory from /opt/cuda/

  It contains only wrapper scripts for nsight-compute, nsight-systems and Sanitizer, which are intended to be placed in $PATH and they are supposed to select the latest version of multiple binaries installed on the system. Arch Linux has only the latest version directly in $PATH so these scripts are not needed.

• Move compute-sanitizer from cuda to cuda-tools and add it to $PATH

• Refactor build function

  Add separate "prepdir" for the cuda-tools package and move stuff there directly (avoids having to repeat the same components twice in package_cuda() for rm and package_cuda-tools for mv). Also some minor style changes.

• Refactor package functions

  Move removing broken links to build() and some minor style changes.