https://fedorahosted.org/sssd/ticket/1495

Implemented working versions of the following functions for libcrypto:
 sss_base64_encode
 sss_base64_decode
 sss_hmac_sha1
 sss_password_encrypt
 sss_password_decrypt

test_encrypt_decrypt now expects EOK from libcrypto.
test_hmac_sha1 now expects EOK from libcrypto.
Added test_base64_encode to test base64 encoding implementation.
Added test_base64_decode to test base64 decoding implementation.

Signed-off-by: George McCollister <George.McCollister@gmail.com>

Removed:
    SSS_UNRESOLVED_DEBUG_LEVEL (completely replaced with SSSDBG_UNRESOLVED)

Added new macro:
    CONVERT_AND_SET_DEBUG_LEVEL(new_value)

Changes unresolved debug level value (SSSDBG_UNRESOLVED) from -1 to 0
so DEBUG macro could be reduced by one condition. Anyway, it has a minor
effect, every time you want to load debug_level from command line parameters,
you have to use following pattern:

    /* Set debug level to invalid value so we can deside if -d 0 was used. */
    debug_level = SSSDBG_INVALID;

    pc = poptGetContext(argv[0], argc, argv, long_options, 0);
    while((opt = poptGetNextOpt(pc)) != -1) { ... }

    CONVERT_AND_SET_DEBUG_LEVEL(debug_level);

https://fedorahosted.org/sssd/ticket/925

Conversion of the old debug_level format to the new one.
(only where it was necessary)

Removed:
  SSS_DEFAULT_DEBUG_LEVEL (completely replaced with SSSDBG_DEFAULT)

Adds two utility functions to obfuscate a password and inverse to
extract the cleartext password back.

So far, only NSS-based implementation is provided.