add redirect for renamed top-5-list file

Add the redirect instructions and add whereto as a step in the linters
build to ensure that all redirects are being tested.

Change-Id: Ib8ea0be2e063a7972f3a6ad71c32921512796136
Signed-off-by: Doug Hellmann <doug@doughellmann.com>

doc/source/_extra/.htaccess

@@ -0,0 +1 @@
+redirect 301 /tc/reference/top-5-help-wanted.html /tc/reference/help-most-needed.html

doc/test/redirect-tests.txt

@@ -0,0 +1 @@
+/tc/reference/top-5-help-wanted.html 301 /tc/reference/help-most-needed.html

test-requirements.txt

@@ -6,3 +6,4 @@ yamllint>=0.5.2
 requests-cache
 Pillow>=2.4.0 # PIL License
 hacking!=0.13.0,<0.14,>=0.12.0 # Apache-2.0
+whereto>=0.3.0  # Apache-2.0

tox.ini

@@ -19,6 +19,7 @@ commands =
             -print0 | xargs -0 yamllint"
            {toxinidir}/tools/check_projects_yaml_alphabetized.sh
   flake8
+  whereto {toxinidir}/doc/source/_extra/.htaccess {toxinidir}/doc/test/redirect-tests.txt
 
 [testenv:venv]
 commands = {posargs}