Clean up dependencies

This change specifies the dependencies directly in setup.py, instead of
in a requirements.txt file that is parsed by a helper function.

requirements.txt

@@ -1,5 +0,0 @@
-pycurl
-cryptography
-rpkg
-six
-GitPython

setup.py

@@ -1,34 +1,5 @@
 from setuptools import setup
 
-def get_requirements(requirements_file="requirements.txt"):
-    """Get the contents of a file listing the requirements.
-
-    :arg requirements_file: path to a requirements file
-    :type requirements_file: string
-    :returns: the list of requirements, or an empty list if
-              `requirements_file` could not be opened or read
-    :return type: list
-    """
-
-    lines = open(requirements_file).readlines()
-    dependencies = []
-    for line in lines:
-        maybe_dep = line.strip()
-        if maybe_dep.startswith("#"):
-            # Skip pure comment lines
-            continue
-        if maybe_dep.startswith("git+"):
-            # VCS reference for dev purposes, expect a trailing comment
-            # with the normal requirement
-            __, __, maybe_dep = maybe_dep.rpartition("#")
-        else:
-            # Ignore any trailing comment
-            maybe_dep, __, __ = maybe_dep.partition("#")
-        # Remove any whitespace and assume non-empty results are dependencies
-        maybe_dep = maybe_dep.strip()
-        if maybe_dep:
-            dependencies.append(maybe_dep)
-    return dependencies
 
 setup(
     name="centpkg",
@@ -39,6 +10,12 @@ setup(
     license="GPLv2+",
     package_dir={'': 'src'},
     packages=['centpkg'],
-    install_requires=get_requirements(),
+    install_requires=[
+        'cryptography',
+        'GitPython',
+        'pycurl',
+        'rpkg',
+        'six',
+    ],
     scripts=['src/bin/centpkg', 'src/bin/centpkg-sig'],
 )