Added documentation

Adds documentation for the UUID validator

Author: weierophinney

doc/book/set.md

@@ -29,6 +29,7 @@ The following validators come with the zend-validator distribution.
 - [StringLength](validators/string-length.md)
 - [Timezone](validators/timezone.md)
 - [Uri](validators/uri.md)
+- [Uuid](validators/uuid.md)
 
 ## Additional validators
 

doc/book/validators/uuid.md

@@ -0,0 +1,38 @@
+# UUID Validator
+
+`Zend\Validator\Uuid` allows validating [Universally Unique IDentifiers](https://en.wikipedia.org/wiki/Universally_unique_identifier)
+(UUIDs). UUIDs are 128-bit values that are guaranteed to be "practically unique"
+in order to help prevent identifier conflicts. Five separate UUID versions
+exist:
+
+- Version 1, which uses a combination of date-time and hardware MAC addresses to
+  generate the hash.
+- Version 2, which uses a combination of date-time and system user/group identifiers.
+- Version 3, which uses an MD5sum of a URI or distinguished name to generate the
+  hash.
+- Version 4, which uses a CSPRNG to generate the hash.
+- Version 5, which uses the same idea as Version 3, but using SHA-1 for hashing.
+
+The `Uuid` validator is capable of validating whether a string is a valid UUID
+of any version. It does not validate that the UUID exists in your system,
+however, only that it is well-formed.
+
+> ### Introduced in 2.8.0
+>
+> `Zend\Validator\Uuid` was introduced with version 2.8.0.
+
+## Supported options
+
+The `Uuid` validator has no additional options.
+
+## Basic usage
+
+```php
+$validator = new Zend\Validator\Uuid();
+
+if ($validator->isValid($uuid)) {
+    // UUID was valid
+} else {
+    // Invalid/mal-formed UUID; use $validator->getMessages() for more detail
+}
+```

mkdocs.yml

@@ -35,6 +35,7 @@ pages:
             - StringLength: validators/string-length.md
             - Timezone: validators/timezone.md
             - Uri: validators/uri.md
+            - Uuid: validators/uuid.md
         - "File Validators":
             - Intro: validators/file/intro.md
             - Count: validators/file/count.md