Use greater than or equal to in requirements. (#6117)

* Use greater than or equal to in requirements.

This changes the existing requirements using strictly greater than to greater
than or equal to so that they're more conventional.

* Use >= for certbot-postfix.

Despite it previously saying 'certbot>0.23.0', certbot-postfix/local-oldest-requirements.txt was pinned to 0.23.0 so let's just use certbot>=0.23.0.

certbot-apache/setup.py

@@ -7,8 +7,8 @@ version = '0.26.0.dev0'
 # Remember to update local-oldest-requirements.txt when changing the minimum
 # acme/certbot version.
 install_requires = [
-    'acme>0.24.0',
-    'certbot>0.25.1',
+    'acme>=0.25.0',
+    'certbot>=0.26.0.dev0',
     'mock',
     'python-augeas',
     'setuptools',

certbot-dns-route53/setup.py

@@ -6,7 +6,7 @@ version = '0.26.0.dev0'
 # Remember to update local-oldest-requirements.txt when changing the minimum
 # acme/certbot version.
 install_requires = [
-    'acme>0.24.0',
+    'acme>=0.25.0',
     'certbot>=0.21.1',
     'boto3',
     'mock',

certbot-nginx/setup.py

@@ -8,7 +8,7 @@ version = '0.26.0.dev0'
 # acme/certbot version.
 install_requires = [
     'acme>=0.25.0',
-    'certbot>0.21.1',
+    'certbot>=0.22.0',
     'mock',
     'PyOpenSSL',
     'pyparsing>=1.5.5',  # Python3 support; perhaps unnecessary?

certbot-postfix/setup.py

@@ -6,7 +6,7 @@ version = '0.26.0.dev0'
 
 install_requires = [
     'acme>=0.25.0',
-    'certbot>0.23.0',
+    'certbot>=0.23.0',
     'setuptools',
     'six',
     'zope.component',

setup.py

@@ -32,7 +32,7 @@ version = meta['version']
 # specified here to avoid masking the more specific request requirements in
 # acme. See https://github.com/pypa/pip/issues/988 for more info.
 install_requires = [
-    'acme>0.24.0',
+    'acme>=0.25.0',
     # We technically need ConfigArgParse 0.10.0 for Python 2.6 support, but
     # saying so here causes a runtime error against our temporary fork of 0.9.3
     # in which we added 2.6 support (see #2243), so we relax the requirement.