Release 1.3.1.

* configure.ac: Set LT version to C19/A11/R2.
Post release updates.

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Strip CRs while building the oid translation table.

* tests/Makefile.am (oidtranstbl.h): Strip CRs
Drop build-system related files

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Update .gitignore

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Merge _ksba_keyinfo_to_sexp into cryptval_to_sexp

* src/keyinfo.c (cryptval_to_sexp): Add mode 2 support suitable to
  replace parse keyinfo data.
* src/keyinfo.c (_ksba_keyinfo_to_sexp): Use new cryptval_to_sexp
  mode dedicated to keyinfo parsing.

--
_ksba_keyinfo_to_sexp and cryptval_to_sexp share lots of common code.
Merge them to be less error prone.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Merge functions that convert from sexp to der

* src/keyinfo.c (cryptval_from_sexp): New. Contains code merged from
  _ksba_keyinfo_from_sexp and _ksba_algoinfo_from_sexp functions.
* src/keyinfo.c (_ksba_algoinfo_from_sexp, _ksba_keyinfo_from_sexp): Use
  cryptval_from_sexp function.

--
Merge two functions translating S-expressions to DER representation.
They share great amount of code, so merge is benefitable.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Add function to parse private key information

* src/keyinfo.c (privkey_algo_table): Add a table with private key
  description.
* src/keyinfo.c (cryptval_to_sexp): Add mode 3 that parses private keys
  according to privkey_algo_table.
* src/keyinfo.c (_ksba_privkey_to_sexp): Parse der via cryptval_to_sexp.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Add PKCS#8 private key parsing support

* src/ksba.h (ksba_priv_key_s, ksba_priv_key_t): New.
* src/privkey.c: New.
* src/tmttv2.asn (PrivateKeyInfo, PrivateKey): Add from RFC 5208.
* src/visibility.c (ksba_priv_key_new, ksba_priv_key_release,
  ksba_priv_key_parse_der, ksba_priv_key_get_private_key): New.
* tests/t-privkey.c: Simple information dumper for private keys.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Don't add dummy extension, if certificate contained no extensions

* src/cert.c (read_extensions): Handle a case where ASN parser added
  explicit empty extension as if there were no extensions at all.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
cryptval_to_sexp: add ability to skip the element in DER

* src/keyinfo.c (cryptval_to_sexp): if elem points to underscore skip
  the current DER element.

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Add initial Gost support

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>