Adding support for optional Password Policy (#3032)

* adds resetTokenValidityDuration setting

* adds a validator to validate password that can be used to enforce strong
passwords

* adds unit tests for passwordPolicy.validator

* adds unit tests to to fail reset password function if password is not in a valid format

* updates README.md for passwordPolicy

* prevents duplicate check for password validator in updateUserPassword

* adds optional setting to disallow username in password

* updates test cases to use fdescribe instead of describe

* updates test cases to use request-promise instead of request

* adds ability to use a RegExp or Callback function or both for a passwordPolicy.validator

* expect username parameter in redirect to password_reset_success

* adds support for _perishable_token_expires_at in postgres

src/Adapters/Storage/Postgres/PostgresStorageAdapter.js

@@ -466,6 +466,7 @@ export class PostgresStorageAdapter {
       fields._account_lockout_expires_at = {type: 'Date'};
       fields._failed_login_count = {type: 'Number'};
       fields._perishable_token = {type: 'String'};
+      fields._perishable_token_expires_at = {type: 'Date'};
     }
     let index = 2;
     let relations = [];
@@ -691,7 +692,8 @@ export class PostgresStorageAdapter {
           }
         }
 
-        if (fieldName === '_account_lockout_expires_at') {
+        if (fieldName === '_account_lockout_expires_at'||
+            fieldName === '_perishable_token_expires_at') {
           if (object[fieldName]) {
             valuesArray.push(object[fieldName].iso);
           } else {
@@ -1068,6 +1070,10 @@ export class PostgresStorageAdapter {
       if (object._account_lockout_expires_at) {
         object._account_lockout_expires_at = { __type: 'Date', iso: object._account_lockout_expires_at.toISOString() };
       }
+      if (object._perishable_token_expires_at) {
+        object._perishable_token_expires_at = { __type: 'Date', iso: object._perishable_token_expires_at.toISOString() };
+      }
+
 
       for (let fieldName in object) {
         if (object[fieldName] === null) {