Fix KRB5_KDC having inconsistent name, and disable validation when sp…

…ecified as part of custom krb5.conf

Fix issue around ticket refreshes failing

Add ability to supply different krb5 based on environment

Add support for credhub binding of kerberos credentials on cloud foundry

Add support for embedded custom krb5.conf

Add ability to provide user specific krb5

Print out buildpack version when it runs

Fix env vars not being properly setup by buildpack

Add troubleshooting guide, add kdc test to sample app

more notes