Merge pull request #363 from Incogdino/branch-updateEmailErrorMessage

Update email restrictions

docs/UserGuide.md

@@ -236,8 +236,10 @@ Eg. `n/John` or `name/john`
 
 <md>**Email restrictions**</md>
 Emails should be of the format `local-part@domain` and adhere to the following constraints:
-1. `local-part` should only contain English alphanumeric characters and `+`, `_` , `.` , `-`. 
-2. `local-part` may not start or end with any special characters.
+1. `local-part` should only contain English alphanumeric characters and `+`, `_` , `.` , `-`.
+The `local-part` name:
+    - may not start or end with any special characters.
+    - may not have any consecutive special characters.
 3. This is followed by an `@` and then a `domain` name. The domain name is made up of domain labels separated by periods.
 The `domain name` must:
     - end with a domain label at least 2 characters long

src/main/java/seedu/address/model/person/Email.java

@@ -13,8 +13,10 @@ public class Email {
     public static final String MESSAGE_CONSTRAINTS = "Emails should be of the format local-part@domain "
             + "and adhere to the following constraints:\n"
             + "1. The local-part should only contain alphanumeric characters and these special characters, excluding "
-            + "the parentheses, (" + SPECIAL_CHARACTERS + "). The local-part may not start or end with any special "
-            + "characters.\n"
+            + "the parentheses, (" + SPECIAL_CHARACTERS + ").\n"
+            + "The local-part name:\n"
+            + "    - May not start or end with any special characters.\n"
+            + "    - May not have any consecutive special characters.\n"
             + "2. This is followed by a '@' and then a domain name. The domain name is made up of domain labels "
             + "separated by periods.\n"
             + "The domain name must:\n"