Added a PHPUnit configuration file.
Added a phpunit.xml.dist and custom bootstrap file.
Added info to README on how to run PHPUnit tests.
Custom configuration file required due to https://www.drupal.org/node/2499239 - Core configuration file does not discover submodule PHPTests (ie. those located in modules/mymodule/modules/mysubmodule/
Issue #2679459 by dpi: Removed sms_user_get_number() and sms_user_send()
Fixed SMS Blast working with entity phone numbers
phone number provider no longer sends a message to every phone number on an entity
createEntityWithPhoneNumber now correctly detects entity type depending on passed settings.