vendor test tools in submodule

Instead of using the main module we should vendor the test tools in a
different directory. That way we do not add extra dependencies to the
main module which can be problemetic for packages or other users.

This is already done in buildah so this makes us more consitent.

Signed-off-by: Paul Holzinger <pholzing@redhat.com>

test/tools/vendor/github.com/vbatts/git-validation/README.md

@@ -0,0 +1,106 @@
+# git-validation
+
+A way to do validation on git commits.
+[![Build Status](https://travis-ci.org/vbatts/git-validation.svg?branch=master)](https://travis-ci.org/vbatts/git-validation)
+
+## install
+
+```console
+vbatts@valse ~ (master) $ go get -u github.com/vbatts/git-validation
+```
+
+## usage
+
+The flags
+```console
+vbatts@valse ~/src/vb/git-validation (master *) $ git-validation -h
+Usage of git-validation:
+  -D    debug output
+  -d string
+        git directory to validate from (default ".")
+  -list-rules
+        list the rules registered
+  -range string
+        use this commit range instead
+  -run string
+        comma delimited list of rules to run. Defaults to all.
+  -v    verbose
+```
+
+The entire default rule set is run by default:
+```console
+vbatts@valse ~/src/vb/git-validation (master) $ git-validation -list-rules
+"dangling-whitespace" -- checking the presence of dangling whitespaces on line endings
+"DCO" -- makes sure the commits are signed
+"message_regexp" -- checks the commit message for a user provided regular expression
+"short-subject" -- commit subjects are strictly less than 90 (github ellipsis length)
+```
+
+Or, specify comma-delimited rules to run:
+```console
+vbatts@valse ~/src/vb/git-validation (master) $ git-validation -run DCO,short-subject
+ * b243ca4 "README: adding install and usage" ... PASS
+ * d614ccf "*: run tests in a runner" ... PASS
+ * b9413c6 "shortsubject: add a subject length check" ... PASS
+ * 5e74abd "*: comments and golint" ... PASS
+ * 07a982f "git: add verbose output of the commands run" ... PASS
+ * 03bda4b "main: add filtering of rules to run" ... PASS
+ * c10ba9c "Initial commit" ... PASS
+```
+
+Verbosity shows each rule's output:
+```console
+vbatts@valse ~/src/vb/git-validation (master) $ git-validation -v
+ * d614ccf "*: run tests in a runner" ... PASS
+  - PASS - has a valid DCO
+  - PASS - commit subject is 72 characters or less! *yay*
+ * b9413c6 "shortsubject: add a subject length check" ... PASS
+  - PASS - has a valid DCO
+  - PASS - commit subject is 72 characters or less! *yay*
+ * 5e74abd "*: comments and golint" ... PASS
+  - PASS - has a valid DCO
+  - PASS - commit subject is 72 characters or less! *yay*
+ * 07a982f "git: add verbose output of the commands run" ... PASS
+  - PASS - has a valid DCO
+  - PASS - commit subject is 72 characters or less! *yay*
+ * 03bda4b "main: add filtering of rules to run" ... PASS
+  - PASS - has a valid DCO
+  - PASS - commit subject is 72 characters or less! *yay*
+ * c10ba9c "Initial commit" ... PASS
+  - PASS - has a valid DCO
+  - PASS - commit subject is 72 characters or less! *yay*
+```
+
+Here's a failure:
+```console
+vbatts@valse ~/src/vb/git-validation (master) $ git-validation 
+ * 49f51a8 "README: adding install and usage" ... FAIL
+  - FAIL - does not have a valid DCO
+ * d614ccf "*: run tests in a runner" ... PASS
+ * b9413c6 "shortsubject: add a subject length check" ... PASS
+ * 5e74abd "*: comments and golint" ... PASS
+ * 07a982f "git: add verbose output of the commands run" ... PASS
+ * 03bda4b "main: add filtering of rules to run" ... PASS
+ * c10ba9c "Initial commit" ... PASS
+1 issues to fix
+vbatts@valse ~/src/vb/git-validation (master) $ echo $?
+1
+```
+
+Excluding paths that are out of the scope of your project:
+```console
+vbatts@valse ~/src/vb/git-validation (master) $ GIT_CHECK_EXCLUDE="./vendor:./git/testdata" git-validation -q -run dangling-whitespace
+...
+```
+using the `GIT_CHECK_EXCLUDE` environment variable. Multiple paths should be separated by colon(`:`)
+
+
+## Rules
+
+Default rules are added by registering them to the `validate` package.
+Usually by putting them in their own package.
+See [`./rules/`](./rules/).
+Feel free to contribute more.
+
+Otherwise, by using `validate` package API directly, rules can be handed directly to the `validate.Runner`.
+