Added call_option which has been needed for a while but was missing

src/call_option.f90

@@ -0,0 +1,18 @@
+subroutine call_option(option, arg_pos)
+    use parameters
+    use opt_disl
+    use opt_group
+    implicit none
+
+    integer, intent(inout) :: arg_pos
+    character(len=100), intent(in) :: option
+
+    select case(trim(adjustl(option)))
+    case('-dislgen', '-disloop')
+        call dislocation(option, arg_pos)
+    case('-group')
+        call group(arg_pos)
+    case default
+        print *, 'Option ', trim(adjustl(option)), ' is not currently accepted.'
+    end select
+end subroutine call_option