add --version option and __version__ module variable and use ~git version suffix

setup.py

@@ -1,8 +1,10 @@
 from setuptools import setup
 
+VERSION="0.1.6~git"
+
 setup (
     name='img2pdf',
-    version='0.1.5',
+    version=VERSION,
     author = "Johannes 'josch' Schauer",
     author_email = 'j.schauer@email.de',
     description = "Convert images to PDF via direct JPEG inclusion.",
@@ -24,7 +26,7 @@ setup (
         'Natural Language :: English',
         'Operating System :: OS Independent'],
     url = 'https://github.com/josch/img2pdf',
-    download_url = 'https://github.com/josch/img2pdf/archive/0.1.5.tar.gz',
+    download_url = 'https://github.com/josch/img2pdf/archive/'+VERSION+'.tar.gz',
     package_dir={"": "src"},
     py_modules=['img2pdf', 'jp2'],
     include_package_data = True,

src/img2pdf.py

@@ -17,6 +17,8 @@
 # License along with this program.  If not, see
 # <http://www.gnu.org/licenses/>.
 
+__version__ = "0.1.6~git"
+
 import sys
 import zlib
 import argparse
@@ -410,6 +412,9 @@ parser.add_argument(
     '-D', '--nodate', help='do not add timestamps', action="store_true")
 parser.add_argument(
     '-v', '--verbose', help='verbose mode', action="store_true")
+parser.add_argument(
+    '-V', '--version', action='version', version='%(prog)s '+__version__,
+    help="Print version information and exit")
 
 def main(args=None):
     if args is None: