Fix Olympus crash

[atsakiridis]

Here's the session:

https://app.testfairy.com/projects/3369662-restcommolympus/builds/4345950/sessions/11

And here's the stacktrace:

java.lang.NullPointerException: Attempt to invoke virtual method 'boolean java.lang.String.equals(java.lang.Object)' on a null object reference
    at org.restcomm.android.olympus.MainActivity.onNewIntent(MainActivity.java:186)
    at android.app.Instrumentation.callActivityOnNewIntent(Instrumentation.java:1213)
    at android.app.Instrumentation.callActivityOnNewIntent(Instrumentation.java:1225)
    at android.app.ActivityThread.deliverNewIntents(ActivityThread.java:2593)
    at android.app.ActivityThread.performNewIntents(ActivityThread.java:2605)
    at android.app.ActivityThread.handleNewIntent(ActivityThread.java:2614)
    at android.app.ActivityThread.access$1700(ActivityThread.java:154)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1463)
    at android.os.Handler.dispatchMessage(Handler.java:102)
    at android.os.Looper.loop(Looper.java:234)
    at android.app.ActivityThread.main(ActivityThread.java:5526)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)