RFR 8182118: Package summary is missing in jdk.security.auth module

[Weijun Wang]

Hi All

Please take a review at
   http://cr.openjdk.java.net/~weijun/8182118/webrev.00/

Basically, a description line is added into package-info.java of each of 
these packages:

- com/sun/security/auth:

  Contains the implementation of {@code java.security.Principal}.

- com/sun/security/auth/module:

  Contains the implementation of {@code 
javax.security.auth.spi.LoginModule}.

- com/sun/security/auth/login:

  Contains the implementation of {@code 
javax.security.auth.login.Configuration}.

- com/sun/security/auth/callback:

  Contains the implementation of {@code 
javax.security.auth.callback.Callback}.

with @since 1.4.

I thought about using {@link java.security.Principal} but seems it's not 
supported in package-info.java.

BTW, is this bug meant for JDK 9? I just read the mail from Mark saying 
only P1 fixes will be allowed from now on.

Thanks
Max