FindMPI: Fix documentation formatting

Adjust whitespace to make the output of "--help-module FindMPI" look
good.  Also separate the comment containing the copyright and license
notice so it does not appear in the documentation.

Modules/FindMPI.cmake

@@ -1,6 +1,4 @@
-# - Message Passing Interface (MPI) module.
+# - Find a Message Passing Interface (MPI) implementation
-#
-#=============================================================================
 # The Message Passing Interface (MPI) is a library used to write
 # high-performance distributed-memory parallel applications, and
 # is typically deployed on a cluster. MPI is a standard interface
@@ -9,43 +7,38 @@
 # libraries to link against, etc., and this module tries to smooth
 # out those differences.
 #
-#=== Variables ===============================================================
+# === Variables ===
+#
 # This module will set the following variables per language in your project,
 # where <lang> is one of C, CXX, or Fortran:
-#
 #   MPI_<lang>_FOUND           TRUE if FindMPI found MPI flags for <lang>
 #   MPI_<lang>_COMPILER        MPI Compiler wrapper for <lang>
 #   MPI_<lang>_COMPILE_FLAGS   Compilation flags for MPI programs
 #   MPI_<lang>_INCLUDE_PATH    Include path(s) for MPI header
 #   MPI_<lang>_LINK_FLAGS      Linking flags for MPI programs
 #   MPI_<lang>_LIBRARIES       All libraries to link MPI programs against
-#
 # Additionally, FindMPI sets the following variables for running MPI
 # programs from the command line:
-#
 #   MPIEXEC                    Executable for running MPI programs
-#   MPIEXEC_NUMPROC_FLAG       Flag to pass to MPIEXEC before giving it the
+#   MPIEXEC_NUMPROC_FLAG       Flag to pass to MPIEXEC before giving
-#                              number of processors to run on
+#                              it the number of processors to run on
-#   MPIEXEC_PREFLAGS           Flags to pass to MPIEXEC directly before the
+#   MPIEXEC_PREFLAGS           Flags to pass to MPIEXEC directly
-#                              executable to run.
+#                              before the executable to run.
-#   MPIEXEC_POSTFLAGS          Flags to pass to MPIEXEC after other flags.
+#   MPIEXEC_POSTFLAGS          Flags to pass to MPIEXEC after other flags
+# === Usage ===
 #
-#=== Usage ===================================================================
 # To use this module, simply call FindMPI from a CMakeLists.txt file, or
 # run find_package(MPI), then run CMake.  If you are happy with the auto-
 # detected configuration for your language, then you're done.  If not, you
 # have two options:
-#
 #   1. Set MPI_<lang>_COMPILER to the MPI wrapper (mpicc, etc.) of your
 #      choice and reconfigure.  FindMPI will attempt to determine all the
 #      necessary variables using THAT compiler's compile and link flags.
-#
 #   2. If this fails, or if your MPI implementation does not come with
 #      a compiler wrapper, then set both MPI_<lang>_LIBRARIES and
-#      MPI_<lang>_INCLUDE_PATH.  You may also set any other variables listed
+#      MPI_<lang>_INCLUDE_PATH.  You may also set any other variables
-#      above, but these two are required.  This will circumvent
+#      listed above, but these two are required.  This will circumvent
 #      autodetection entirely.
-#
 # When configuration is successful, MPI_<lang>_COMPILER will be set to the
 # compiler wrapper for <lang>, if it was found.  MPI_<lang>_FOUND and other
 # variables above will be set if any MPI implementation was found for <lang>,
@@ -53,22 +46,21 @@
 #
 # When using MPIEXEC to execute MPI applications, you should typically use
 # all of the MPIEXEC flags as follows:
-#   ${MPIEXEC} ${MPIEXEC_NUMPROC_FLAG} PROCS ${MPIEXEC_PREFLAGS} EXECUTABLE
+#   ${MPIEXEC} ${MPIEXEC_NUMPROC_FLAG} PROCS
-#     ${MPIEXEC_POSTFLAGS} ARGS
+#     ${MPIEXEC_PREFLAGS} EXECUTABLE ${MPIEXEC_POSTFLAGS} ARGS
 # where PROCS is the number of processors on which to execute the program,
 # EXECUTABLE is the MPI program, and ARGS are the arguments to pass to the
 # MPI program.
 #
-#=== Backward Compatibility ==================================================
+# === Backward Compatibility ===
+#
 # For backward compatibility with older versions of FindMPI, these
 # variables are set, but deprecated:
-#
 #   MPI_FOUND           MPI_COMPILER        MPI_LIBRARY
 #   MPI_COMPILE_FLAGS   MPI_INCLUDE_PATH    MPI_EXTRA_LIBRARY
 #   MPI_LINK_FLAGS      MPI_LIBRARIES
-#
 # In new projects, please use the MPI_<lang>_XXX equivalents.
-#
+
 #=============================================================================
 # Copyright 2001-2011 Kitware, Inc.
 # Copyright 2010-2011 Todd Gamblin tgamblin@llnl.gov