Log Message:
Update to 0.3.0:

Version 0.3.0
- Export DER utility functions, mostly so that GnuTLS can avoid using
  libtasn1 internals.
- The _asn1* symbols are not exported in the shared library file (when
  using GNU ld).
- The library can now be built using Visual Studio, and the project
  files are included in windows/.
- New public APIs:
  asn1_get_tag_der
  asn1_octet_der
  asn1_get_octet_der
  asn1_bit_der
  asn1_get_bit_der
  asn1_get_length_der
  asn1_length_der