No gir strict when gobject-introspection less than 1.39

Don't --enable-strict for girscanner when gobject-introspection
is less than 1.39, as it barfs on our headers.
asn1: Fix ASN.1 compilation and update for new libtasn1
gcr: Fix test-parser to treat '6' as normal char in test names

This caused extra underscores in file names that had a 6 in them.
asn1: Added updates to ASN.1 from RFCs 5480 & 5758 & 5915

Signed-off-by: Stef Walter <stefw@gnome.org>
 * Fixed conflicts and combined into one commit
 * Moved to pk.asn since it's EXPLICIT tags by default

https://bugzilla.gnome.org/show_bug.cgi?id=672137
asn1: Add egg_asn1x_get_string_as_usg function

Gets a string as an unsigned integer, removing leading zeros, and
combining strings of indefinite length.
oid: Add various OIDs for Elliptic Curve related stuff
gcr: Move key size code to gcr-subject-public-key.c

Refactor things to key size calculation code is in one place
ui: Print 'Elliptic Curve' as key type for EC keys in renderer
gcr: Implement support for parsing ecdsa OpenSSH keys
gcr: GcrParser support for EC private and public keys
gcr: GcrParser support or PEM 'PUBLIC KEY' files

These contain SubjectPublicKeyInfo
gcr: Add gcr-subject-public-key.c support for EC keys and certs
asn1: More clear dump display whether something has value/not

When dumping parsed DER/ASN.1 tree, print an asterisk if something
has a value, and a dot if it was parsed, but no value.
ui: Add support for EC private PEM keys to our mime magic
ui: Add support for EC keys to key renderer
gcr: Avoid prompts when running 'make distcheck'