The original sprig-library implementation of
genCA and genSignedCert may accept only CN parameter
which isn't enough for K8s admin certificate.
That certification must have O=system:masters, e.g.
/CN=admin/O=system:masters
This PR introduces the set of functions that
insted of cn accept subj argument that may have
a form compatible with openssl -subj parameter.
If the first symbol isn't '/' subj behaves as
cn argument.
The set of new functions that accept subj arg is:
genCAEx
genCAWithKeyEx
genSignedCertEx
genSignedCertWithKeyEx
Since the implementaion required to copy some
non-exported helper functions from sprig,
the decision was made to separate all go-template
extension functions into a separate package:
extlib. This package can be reused in other
go-applications, it's just necessary to use
GenericFuncMap function to get function-map.
Change-Id: I0ffddee2e597323803bf5f1b54f315ded424b7be
