Password validations: Add two new validators

Add two new custom password validators. One ensures
passwords have a minimum number of uppercase letters and the
other ensures passwords have a minimum amount of numbers.

Signed-off-by: Roberto Rosario <roberto.rosario.gonzalez@gmail.com>

docs/chapters/password_validation.rst

@@ -0,0 +1,48 @@
+*******************
+Password validation
+*******************
+
+To help reduce the use of weak passwords, Mayan EDMS includes support for
+password validators. Password validator enforce policies by rejecting
+password that don't conform with the validator's logic.
+
+By default, Mayan EDMS sets this password validation setup:
+
+- That the password is not similar no any user attributes.
+- A minimum password size of 8 characters.
+- The password is not one of the 20,000 commonly used weak password.
+- That the password is not entirely numeric.
+
+This default is coded in the following manner by the default Python setup file::
+
+    AUTH_PASSWORD_VALIDATORS = [
+        {
+            'NAME': 'django.contrib.auth.password_validation.UserAttributeSimilarityValidator',
+        },
+        {
+            'NAME': 'django.contrib.auth.password_validation.MinimumLengthValidator',
+        },
+        {
+            'NAME': 'django.contrib.auth.password_validation.CommonPasswordValidator',
+        },
+        {
+            'NAME': 'django.contrib.auth.password_validation.NumericPasswordValidator',
+        },
+    ]
+
+If using the YAML configuration file the same setup would be coded in the
+following manner::
+
+    AUTH_PASSWORD_VALIDATORS:
+    - NAME: django.contrib.auth.password_validation.UserAttributeSimilarityValidator
+    - NAME: django.contrib.auth.password_validation.MinimumLengthValidator
+    - NAME: django.contrib.auth.password_validation.CommonPasswordValidator
+    - NAME: django.contrib.auth.password_validation.NumericPasswordValidator
+
+In addition to the password validators provided by Django
+:django-docs:`validators provided by Django <topics/auth/passwords/#included-validators>`,
+Mayan EDMS adds the following validators:
+
+.. autoclass:: mayan.apps.authentication.validators.MinimumCapitalLettersContentValidator
+
+.. autoclass:: mayan.apps.authentication.validators.MinimumNumberContentValidator

docs/topics/advanced.rst

@@ -8,3 +8,4 @@ Advanced topics
 .. include:: ../chapters/metadata.rst
 .. include:: ../chapters/transformations.rst
 .. include:: ../chapters/versioning.rst
+.. include:: ../chapters/password_validation.rst