Add krb5_init_context_profile API.

https://github.com/krb5/krb5/commit/f2004cdbca0cb79dc15ad3b91fc375c1dd687608
Commit By: ghudson
Revision: 25026
Changed Files:
U   trunk/src/include/k5-int.h
U   trunk/src/include/krb5/krb5.hin
U   trunk/src/lib/krb5/krb/init_ctx.c
U   trunk/src/lib/krb5/libkrb5.exports
U   trunk/src/lib/krb5/os/init_os_ctx.c
U   trunk/src/lib/krb5_32.def