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Add EXTERNAL tags for INTEGERs
Fix P3 byte string for DerSequence
Add ability to read in RSA keys from X.509 certs
Add validation flag for import from X.509 cert

This patch forces the user to explicitly assert
that no validation of the X.509 certificate will be
done when importing an RSA key.

In other words, public keys can only be imported in the following way:

    >>> cert_data = open("cert.pem", "rb").read()
    >>> key = RSA.importKey(cert_data, verify_x509_cert=False)

Not passing the parameter "verify_x509_cert" will raise an exception.
DSA keys can be loaded from X.509 certificates
Remove import from X.509 certificates from future plans
Merge branch 'importKey_x509'
First implementation based on int
Added file for GMP backend
Initial support for GMP
Install ctypes with Python 2.4
Fix problem with 64-bit machines and ctypes (long)
Workaround for pip bug (wrong permission after unpacking)
Stricter definitions for parameters to C calls
Added exponentiation to Natural
Unit test will cover both Natural implementations
Added more methods to Natural

Methods and operators added:
* random()
* and
* comparison
* bool
* in-place right shift
* size_in_bits()
* str
* is_even()
* is_odd()
Miller-Rabin test
Add is_perfect_square method to Natural