A simple demonstration of accessing the GSL routines using
the extern block functionality of Chapel.

This test requires:
  * CHPL_LLVM!=none (since the test uses extern blocks)
and a GSL installation detected like so:
  * GSL_DIR environment variable is set, OR
  * GSL dynamic library is detected

Note that if the dynamic library is found, this
test assumes that the header and static library are available.

GSL_DIR can be set, such that $GSL_DIR/include and
$GSL_DIR/lib point to the location of the headers and libraries.

