Update shell scripts for Jenkins automated build and testing

In the new Jenkins project settings, we will have three projects to support different build/test tasks.

* The "dist" project simply creates distribution tarball that is used by the other projects.
* The "valgrind" project performs "make check" to run all test cases. They are run using Valgrind so that we can find memory management defects as well.
* The "distcheck" project performs "make distcheck" to create distribution tarballs (of all distribution types) and test the integrity of the tarballs.

The shell script for the old standalone project is removed.