Fix initials logic (#361)

* Fix initials logic

Fixes #360 

This feels like the correct logic to me but I'm happy to be contradicted - the display name stuff is what is erroring

* Fix build issues

Fix build issues

Author: RobPethick

src/components/mgt-person/mgt-person.ts

@@ -569,6 +569,10 @@ export class MgtPerson extends MgtTemplatedComponent {
       person = this.personDetails;
     }
 
+    if ((person as MicrosoftGraph.Contact).initials) {
+      return (person as MicrosoftGraph.Contact).initials;
+    }
+
     let initials = '';
     if (person.givenName) {
       initials += person.givenName[0].toUpperCase();
@@ -578,9 +582,9 @@ export class MgtPerson extends MgtTemplatedComponent {
     }
 
     if (!initials && person.displayName) {
-      const name = person.displayName.split(' ');
+      const name = person.displayName.split(/\s+/);
       for (let i = 0; i < 2 && i < name.length; i++) {
-        if (name[i][0].match(/[a-z]/i)) {
+        if (name[i][0] && name[i][0].match(/[a-z]/i)) {
           // check if letter
           initials += name[i][0].toUpperCase();
         }