Add rule for pip_install permission fix (#895)

* Add rule for pip_install permission fix

* Fix whitespace

* Switch quotation to single

* remove 2nd else

* E261 indent comment

tests/rules/test_pip_install.py

@@ -0,0 +1,27 @@
+# -*- coding: UTF-8 -*-
+from thefuck.rules.pip_install import match, get_new_command
+from thefuck.types import Command
+
+
+def test_match():
+    response1 = """
+    Could not install packages due to an EnvironmentError: [Errno 13] Permission denied: '/Library/Python/2.7/site-packages/entrypoints.pyc'
+Consider using the `--user` option or check the permissions.
+"""
+    assert match(Command('pip install -r requirements.txt', response1))
+
+    response2 = """
+Collecting bacon
+  Downloading https://files.pythonhosted.org/packages/b2/81/19fb79139ee71c8bc4e5a444546f318e2b87253b8939ec8a7e10d63b7341/bacon-0.3.1.zip (11.0MB)
+    100% |████████████████████████████████| 11.0MB 3.0MB/s
+Installing collected packages: bacon
+  Running setup.py install for bacon ... done
+Successfully installed bacon-0.3.1
+"""
+    assert not match(Command('pip install bacon', response2))
+
+
+def test_get_new_command():
+    assert get_new_command(Command('pip install -r requirements.txt', '')) == 'pip install --user -r requirements.txt'
+    assert get_new_command(Command('pip install bacon', '')) == 'pip install --user bacon'
+    assert get_new_command(Command('pip install --user -r requirements.txt', '')) == 'sudo pip install -r requirements.txt'