Factor out sql requirements

MANIFEST.in

@@ -1 +1 @@
-include requirements.txt LICENSE.txt sql/**/*
+include *requirements.txt LICENSE.txt sql/**/*

requirements.txt

@@ -1,5 +1,3 @@
-psycopg2==2.8.6
-SQLAlchemy==1.3.20
 confini~=0.3.6rc3
 semver==2.13.0
 hexathon~=0.0.1a7

setup.py

@@ -2,6 +2,7 @@ from setuptools import setup
 import configparser
 import os
 
+
 requirements = []
 f = open('requirements.txt', 'r')
 while True:
@@ -11,6 +12,19 @@ while True:
     requirements.append(l.rstrip())
 f.close()
 
+sql_requirements = []
+f = open('sql_requirements.txt', 'r')
+while True:
+    l = f.readline()
+    if l == '':
+        break
+    sql_requirements.append(l.rstrip())
+f.close()
+
+
 setup(
     install_requires=requirements,
+    extras_require={
+        'sql': sql_requirements,
+    }
     )