docs: Update makefiles to current Sphinx version
docs: Remove references to django-compressor
install -d works on vcs links fix #798 fix #1060
remove duplicate 'if cr == (0, 0):' in get_terminal_size
Merge pull request #1941 from mekarpeles/I1939/hotfix/duplicate-code

remove duplicate 'if cr == (0, 0):' in get_terminal_size
minor fixes to changelog
Raise NotImplementedError (not NotImplemented)

NotImplemented is a singleton intended for use in __eq__ methods where comparison is not possible for some reason.
Merge pull request #1947 from mjg123/patch-1

Raise NotImplementedError (not NotImplemented)
Merge pull request #1627 from techtonik/develop

Update sphinx-generated doc build files
Revert "Merge pull request #1519 from dstufft/remove-dependency-links"

This reverts commit da02f073dabdc9e72733847aa1727ec19869109d, reversing
changes made to 2ad8888901c041b8f9aacebb3a16d55bf631e867.

Conflicts:
	CHANGES.txt
	pip/commands/freeze.py
	pip/commands/list.py
	pip/commands/wheel.py
	pip/index.py
	pip/req/req_set.py
	pip/vcs/subversion.py
InstallRequirement.url should preserve the initial value for from_line requirements
a functional test for non-editable vcs installs
pep8 fixes
add missing vcs prefixes
Merge pull request #1955 from dstufft/revert-dep-links-removal

Revert "Merge pull request #1519 from dstufft/remove-dependency-links"
Merge pull request #1926 from jschneier/develop

install -d works on vcs links fix #798 fix #1060
Merge pull request #1956 from qwcode/issue_1952

preserve the full vcs url when using `InstallRequirement.from_line`
Move unpack_url to pip.download

This puts all unpack functions in the same place.
Cherrypicked from a commit of qwcode
Align unpack_http_url to unpack_file_url
pip.download: add docstring and log