Remove coverage

At the moment coverage is causing more trouble than it's worth. Codecov
isn't giving meaningful results and we aren't using coverage to increase
test coverage.

https://github.com/python-ldap/python-ldap/pull/349
Fixes: https://github.com/python-ldap/python-ldap/issues/348
Signed-off-by: Christian Heimes <cheimes@redhat.com>

.travis.yml

@@ -85,14 +85,6 @@ env:
 install:
   - pip install "pip>=7.1.0"
   - pip install tox-travis tox codecov
-  # Coverage 5.0+ has issues similar to:
-  #   https://github.com/nedbat/coveragepy/issues/915
-  - pip install "coverage<5.0"
 
 script: CFLAGS="$CFLAGS_warnings $CFLAGS_std" tox
 
-after_success:
-  # gather Python coverage
-  - python -m coverage combine
-  # send Python and GCOV coverage
-  - codecov

tox.ini

@@ -5,25 +5,22 @@
 
 [tox]
 # Note: when updating Python versions, also change setup.py and .travis.yml
-envlist = py27,py34,py35,py36,py37,py38,py39,{py2,py3}-nosasltls,doc,py3-trace,coverage-report
+envlist = py27,py34,py35,py36,py37,py38,py39,{py2,py3}-nosasltls,doc,py3-trace
 minver = 1.8
 
 [testenv]
-# Coverage 5.0+ has issues similar to:
-#   https://github.com/nedbat/coveragepy/issues/915
-deps = coverage<5.0
+deps =
 passenv = WITH_GCOV
 # - Enable BytesWarning
 # - Turn all warnings into exceptions.
 commands = {envpython} -bb -Werror \
-    -m coverage run --parallel -m unittest discover -v -s Tests -p 't_*'
+    -m unittest discover -v -s Tests -p 't_*'
 
 [testenv:py27]
 # No warnings with Python 2.7
 passenv = {[testenv]passenv}
 commands =
-    {envpython} -m coverage run --parallel \
-        -m unittest discover -v -s Tests -p 't_*'
+    {envpython} -m unittest discover -v -s Tests -p 't_*'
 
 [testenv:py34]
 # No warnings with Python 3.4
@@ -76,16 +73,6 @@ basepython = pypy3.5
 deps = {[testenv:pypy]deps}
 commands = {[testenv:pypy]commands}
 
-[testenv:coverage-report]
-# Coverage 5.0+ has issues similar to:
-#   https://github.com/nedbat/coveragepy/issues/915
-deps = coverage<5.0
-skip_install = true
-commands =
-    {envpython} -m coverage combine
-    {envpython} -m coverage report --show-missing
-    {envpython} -m coverage html
-
 [testenv:doc]
 basepython = python3
 deps =