Test Vector changes

Changed names of existing vectors to be more instructive about what the
key contains, and adapted tests to compensate, which pass. Added public
keys for all encryption types and two new private keys for PEM
serialization, documented in the README.txt in the same folder
Update test-vectors.rst

Updated the readme with custom vectors, although formatting errors seem to exist
Update spelling_wordlist.txt

Added some keywords for vector documentation
Updated spelling_wordlist.txt

Updated the spelling list to allow for RSA in the vectors README.
Merge pull request #1341 from michael-hart/ec_vectors

Test Vector changes