Incorrect +package

Special meta +package should follow regexp:

^[a-z][a-z0-9_]*(\.[a-z0-9_]+)+[0-9a-z_]$

Incorrect:

+package foo
+package foo.x
+package привет, как дела?
+package привет.как

[] > foo

Correct:

+package foo.bar
+package my.awesome.package
+package test.xy

[] > foo