add md5 checksum support to Install.py for LATTE

# used to automate the steps described in the README file in this dir

from __future__ import print_function

import sys,os,re,subprocess

import sys,os,re,subprocess,hashlib

# help message

  -b = download and build the LATTE library

  -p = specify folder of existing LATTE installation

  -m = copy Makefile.lammps.suffix to Makefile.lammps

  -v = set version of LATTE library to download and set up (default = 1.1.1)

  -v = set version of LATTE library to download and set up (default = 1.2.1)

Example:

version = '1.2.1'

# known checksums for different LATTE versions. used to validate the download.

checksums = { \

        '1.1.0' : '533635721ee222d0ed2925a18fb5b294', \

        '1.2.0' : '68bf0db879da5e068a71281020239ae7', \

        '1.2.1' : 'bed76e7e76c545c36dd848a8f1fd35eb' \

        }

# print error message or help

def error(str=None):

    error("Failed to download source code with 'curl' or 'wget'")

  return

def checkmd5sum(md5sum,fname):

    with open(fname,'rb') as fh:

        m = hashlib.md5()

        while True:

            data = fh.read(81920)

            if not data:

                break

            m.update(data)

    fh.close()

    return m.hexdigest() == md5sum

# parse args

args = sys.argv[1:]

  print("Downloading LATTE ...")

  geturl(url,"LATTE.tar.gz")

  # verify downloaded archive integrity via md5 checksum, if known.

  if version in checksums:

    if not checkmd5sum(checksums[version],'LATTE.tar.gz'):

      error("Checksum for LATTE library does not match")

  print("Unpacking LATTE ...")

  if os.path.exists(lattedir):

    cmd = 'rm -rf "%s"' % lattedir