Renamed and tidied lammmps and lsms tests.
Merge pull request #792 from vasslitvinov/rename-lammps-and-lsms-tests

Renamed and tidied lammmps and lsms tests.

Streamline the naming of the test files to be:
  s-XXX -- single-locale version
  m-XXX -- multi-locale version

Before this change the multi-locale version was labeled "parallel"
or "p", which is not accurate.

Before this change there were 3 copies of the multi-locale version,
with .numlocales of 1, 2, and 4, resp.
This change leaves just 1 copy, with .numlocales of 4.
This is consistent with how other multi-locale tests are set up.
As usual, the one multi-locale copy will be tested with -nl 1
when CHPL_COMM==none.

Valgrind testing for m-lammps is delegated to m-lammps.valgrind.chpl
- like it was introduced in #756 for p-lammps-n1.valgrind.chpl
There is no special provision for valgrind testing for LSMS.

To visualize:

test/studies/lammps/shemmy/
# before this change
  // single-locale version
  s-lammps.chpl
  // multi-locale version, for 1,2,4 locales, resp.
  p-lammps-n1.chpl
  p-lammps-n2.chpl
  p-lammps-n4.chpl
  // symlink to multi-locale version for valgrind testing
  p-lammps-n1.valgrind.chpl
# after this change
  // single-locale version - no change
  s-lammps.chpl
  // multi-locale version, .numlocales is 4
  m-lammps.chpl
  // symlink to multi-locale version for valgrind testing
  m-lammps.valgrind.chpl

test/studies/lsms/shemmy/
# before this change
  // single-locale version
  lsms.chpl
  // multi-locale version, for 1,2,4 locales, resp.
  lsms-parallel-n1.chpl
  lsms-parallel-n2.chpl
  lsms-parallel-n4.chpl
# after this change
  // single-locale version
  s-lsms.chpl
  // multi-locale version, .numlocales is 4
  m-lsms.chpl