PHILADELPHIA — Calling for help in a mental health crisis will now be as simple as remembering a new three-digit hotline. The 988 crisis number that goes live nationwide on Saturday is designed to make it easier to get the services currently offered through the 10-digit National Suicide Prevention Lifeline number — 1-800-273-8255 (1-800-273-TALK). That line will still be active. The launch of the new number has been two years in the making. Still, some mental health advocates and providers say many states, including Pennsylvania, don’t have enough resources to respond to an increase in call vo…