USERGRID-1770: updated README.md with instructions for setting Android permissions
USERGRID-1770: updated README.md with instructions for setting Android permissions

RobertWalsh/apigee-android-sdk,apigee/apigee-android-sdk,apigee/apigee-android-sdk,math4youbyusgroupillinois/apigee-android-sdk,RobertWalsh/apigee-android-sdk,math4youbyusgroupillinois/apigee-android-sdk