pull up r25475 and r25479 from trunk

pull up r25475 and r25479 from trunk

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 r25479 | ghudson | 2011-11-19 17:06:15 -0500 (Sat, 19 Nov 2011) | 8 lines

 ticket: 7019

 Improve documentation in preauth_plugin.h

 Also declare the verto_context structure to ensure that it is has the
 proper scope when used as the return type of the event_context
 callback.

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 r25475 | ghudson | 2011-11-14 21:42:58 -0500 (Mon, 14 Nov 2011) | 9 lines

 ticket: 7019
 subject: Make verto context available to kdcpreauth modules
 target_version: 1.10
 tags: pullup

 Add an event_context callback to kdcpreauth.  Adjust the internal KDC
 and main loop interfaces to pass around the event context, and expose
 it to kdcpreauth modules via the rock.

ticket: 7019
version_fixed: 1.10
status: resolved

git-svn-id: svn://anonsvn.mit.edu/krb5/branches/krb5-1-10@25510 dc483132-0cff-0310-8789-dd5450dbe970