Split specific dependecies in extras require

setup.py

@@ -18,20 +18,28 @@ setup(
             'Programming Language :: Python',
     ],
     install_requires=[
-        'email3',
-        'mako',
-        'mysqlclient',
         'progressbar',
-        'psycopg2',
-        'python-dateutil',
-        'python-ldap',
-        'pytz',
     ],
     extras_require={
         'dev': [
             'pytest',
             'pylint',
         ],
+        'ldap': [
+            'python-ldap',
+            'python-dateutil',
+            'pytz',
+        ],
+        'email': [
+            'email3',
+            'mako',
+        ],
+        'pgsql': [
+            'psycopg2',
+        ],
+        'mysql': [
+            'mysqlclient',
+        ],
     },
     author='Benjamin Renard',
     author_email='brenard@zionetrix.net',