JavadocTagsCheck doesn't validate all author tags

[krzyk]

Following example:

**
 * Simple.
 * @author John Smith (john.smith@example.com)
 * @author None
 * @version $Id$
 */
public interface AuthorTag {
}

Should fail, because second author has incorrect format (it doesn't have an email address), but it doesn't.
When you change order of author tags, JavadocTagsCheck will fail.
Fix JavadocTagsCheck to check all @author tags.

[krzyk]

@davvd valid bug

[davvd]

@davvd valid bug

@krzyk I added bug tag to this ticket

[davvd]

@krzyk many thanks for the report, I topped your account for 30 mins, transaction 70054478

[krzyk]

@davvd this is postponed

[davvd]

@davvd this is postponed

@krzyk right, I added "postponed" label

[davvd]

@davvd this is postponed

@krzyk I will assign somebody else to this issue

[mkordas]

@krzyk can you assign me here?

[krzyk]

@davvd assign @mkordas please

[krzyk]

@davvd this is not postponed

[davvd]

@davvd assign @mkordas please

@krzyk done. @mkordas the task is yours, please go ahead

[davvd]

@davvd this is not postponed

@krzyk sure, thanks, I removed "postponed" tag to it

[mkordas]

@davvd please see PR #573

[davvd]

@davvd please see PR #573

@mkordas will take a look, thanks

[mkordas]

@krzyk this was merged in #573, can you close the issue?

[krzyk]

@mkordas thanks

[davvd]

@mkordas done, I added 30 mins in payment 568cea2e2310ad21f7000311, 98 hours and 23 mins spent to complete this

added +30 to your rating, now it is equal to +1375