Fix bash command line in build script (#23)

On some systems, /bin/sh points to dash, which does not support some
bash constructs, like `${BASH_SOURCE[0]}`.  Change #! line to
/bin/bash instead.

Add -e option to stop upon first command that fails.

Co-authored-by: Joel E. Denny <[email protected]>

build_and_run_umt.sh

@@ -1,4 +1,4 @@
-#!/bin/sh -x
+#!/bin/bash -xe
 # This script will compile a basic Release build of UMT.  Additional CMake options can be added to the command line args of this
 # script, and they will be picked up and added to the UMT CMake command at the bottom of this script.
 # For a list of supported CMake options, run 'ccmake /path/to/umt/src'.