cleanup: get rid of most "import *"

Apply script generated with the following hack:
(
hg loc '*.py'|xargs pyflakes-2 | sed -rn "s/([^:]*):.*'(.*)' may be undefined, or defined from star imports.*/sed -ri 's,\\\\<\2\\\\>([^=]|$),XXXX.\2\\\\1,g' \1/gp" | sort -u
hg loc '*.py'|xargs pyflakes-2 | sed -rn "s/([^:]*):.* undefined name '(.*)'$/sed -ri 's,\\\\<\2\\\\>([^=]|$),XXXX.\2\\\\1,g' \1/gp" | sort -u
hg loc '*.py'|xargs pyflakes-2 | sed -rn "s/([^:]*):.*'(from .*)\.([^.]*) import \*' used.*/sed -ri 's,\\\\<XXXX\\\\.,\3.,g' \1/gp" | sort -u
hg loc '*.py'|xargs pyflakes-2 | sed -rn "s/([^:]*):.*'(from .*)\.([^.]*) import \*' used.*/sed -ri 's,\2\\\\.\3 .*,\2 import \3,g' \1/gp" | sort -u
) | grep -v kallithea/bin/kallithea_cli_ishell.py > fix2.sh

py3: add b'' annotations in some places where they will be needed later

Mostly entirely trivial adding of b prefix that is a ignored for py2 ... and
also a bit of related trivial reformatting/refactorings.

auth: add https ability to the crowd auth module (issue #315)

[Thomas De Schampheleire:
- use select iso checkbox to remove need for bool->string conversion
- update tests]

codingstyle: trivial whitespace fixes

Reported by flake8.

auth: make ldap OPT_X_TLS_CACERTDIR configurable

A location was hardcoded. The location was wrong for many systems and prevented
actual TLS from working. Also, it should not be necessary with modern Pythons.

For some reason, instead of removing it, we now decide to expose it to the
user. Choice FTW!

tests: add as little code as possible in __init__.py

kallithea/tests/__init__.py contained quite a lot of code, including the test
base class TestController. This in itself may be considered bad practice.

Specifically, this poses a problem when using pytest 3.0+, in which asserts
in some files are not automatically rewritten to give improved assert
output. That problem can be fixed by explicitly registering such files for
assertion rewriting, but that register call should be executed _before_ said
files are imported. I.e. if the register call is in
kallithea/tests/__init__.py, assert calls in __init__.py itself can not be
rewritten.

Since the TestController base class does effectively contain asserts, and we
do not want to execute the register call from somewhere outside the
kallithea/tests directory, we need to move the TestController class to
another file (kallithea/tests/base.py) so we can have a register call in
__init__.py before loading base.py.

While not strictly necessary to fix the mentioned pytest problem, we take
the opportunity to fully clean __init__.py and move everything to
the new kallithea/tests/base.py. While doing so, unnecessary imports are
removed, and imports are ordered alphabetically. Explicit imports of symbols
from modules that were already imported as a whole, are removed in favor of
fully qualifying the references (e.g. tempfile._RandomNameSequence).

pytest migration: rename TestControllerPytest back to TestController

The name TestControllerPytest was introduced to allow a temporary situation
where nose/unittest and pytest-based tests could coexist.
This situation is now over, so the base test class can be renamed again.

pytest migration: functional: switch to standard assert statements

Use unittest2pytest to replace unittest-style assert statements (e.g.
assertEqual) with standard Python assert statements to benefit from pytest's
improved reporting on assert failures.

The conversion by unittest2pytest was correct, except for line wrapping
problems.

pytest migration: convert simple functional tests to TestControllerPytest

Replace usage of TestController with TestControllerPytest for those files in
tests/functional where there is no setUp/tearDown method (the pytest
equivalent to be investigated) and that do not use test parametrization.

pytest migration: use pytest test skipping instead of nose's

While the nose test skipping still worked, we want to remove all remnants of
nose, so switch to the pytest equivalent.

Note: due to a bug in pytest-sugar (reported at [1]) the skipped tests are
not shown explicitly when using the 'skipif' approach, while they were with
the nose approach. Since pytest-sugar is not enabled yet in setup.py, this
is not deemed a problem.

[1] https://github.com/Frozenball/pytest-sugar/issues/75

tests: basic tests that the pam and crowd auth modules can be enabled

Will at least give a minimal check for syntax errors ...

BaseController: hide "Log out" link for external login sessions

If user is authorized by external means (API key or container auth),
Kallithea is not actually able to log the user out and should not show
the "Log out" link.

BaseController: enable container authentication on all pages

Previously, user had to visit the login page to log in using container
authentication; this now happens on every page load, unless user has an
existing login session.

The container authentication result is cached in session on success.

tests: provide _authentication_token when POSTing

So far not used, just preparing for the the time when the actual checking is
introduced ...

This change is very verbose. self.app.post should perhaps just at this value
automagically ...

Second step in two-part process to rename directories.
This is the actual directory rename.