Revise all lint tests and add consolidated 'linters' tox environment

OpenStack-Infra has requested that lint tests be pipelined into the 'linters'
tox target in order to make more efficient use of nodepool resources.

This patch:

- Ensures that a complete set of lints tests is available in individual
  tox targets.
- Adds a 'linters' target which executes all the other lints tests.

Change-Id: I7a682da5c94534dad4da441dbe285e9a33205a95

tox.ini

@@ -1,7 +1,7 @@
 [tox]
 minversion = 1.6
 skipsdist = True
-envlist = docs,pep8,bashate
+envlist = docs,linters
 
 [testenv]
 usedevelop = True
@@ -18,11 +18,12 @@ commands=
 deps = -r{toxinidir}/test-requirements.txt
 commands = {posargs}
 
-# Run hacking/flake8 check for all python files
 [testenv:pep8]
-deps = flake8
+deps =
+    flake8
 whitelist_externals = bash
 commands =
+    # Run hacking/flake8 check for all python files
     bash -c "grep -Irl \
         -e '!/usr/bin/env python' \
         -e '!/bin/python' \
@@ -36,26 +37,32 @@ commands =
         --exclude '*.sh' \
         {toxinidir} | xargs flake8 --verbose"
 
-
 [flake8]
 # Ignores the following rules due to how ansible modules work in general
-#     F403 'from ansible.module_utils.basic import *' used; unable to detect undefined names
+#     F403 'from ansible.module_utils.basic import *' used;
+#          unable to detect undefined names
 #     H303  No wildcard (*) import.
 ignore=F403,H303
 
-# Run bashate check for all bash scripts
-# Ignores the following rules:
-#     E003: Indent not multiple of 4 (we prefer to use multiples of 2)
 [testenv:bashate]
-deps = bashate
+deps =
+  bashate
 whitelist_externals = bash
 commands =
-    bash -c "grep -Irl \
-        -e '!/usr/bin/env bash' \
-        -e '!/bin/bash' \
-        -e '!/bin/sh' \
-        --exclude-dir '.*' \
-        --exclude-dir '*.egg' \
-        --exclude-dir '*.egg-info' \
-        --exclude 'tox.ini' \
-        {toxinidir} | xargs bashate --verbose --ignore=E003"
+  # Run bashate check for all bash scripts
+  # Ignores the following rules:
+  #     E003: Indent not multiple of 4 (we prefer to use multiples of 2)
+  bash -c "grep --recursive --binary-files=without-match \
+    --files-with-match '^.!.*\(ba\)\?sh$' \
+    --exclude-dir .tox \
+    --exclude-dir .git \
+    {toxinidir} | xargs bashate --error . --verbose --ignore=E003"
+
+[testenv:linters]
+deps =
+  {[testenv:pep8]deps}
+  {[testenv:bashate]deps}
+whitelist_externals = bash
+commands =
+  {[testenv:pep8]commands}
+  {[testenv:bashate]commands}