add rsa_generate_private_key function to replace RSAPrivateKey.generate

refs #1026. #1101 is dependent on this
fix coverage
more coverage...
add some missing docs
rename the function
rename the docs too.
Simplified code
Multibackend support for EC
Add EC to changelog
Fix syntax error in docs
Merge pull request #1108 from alex/simplify-code

Simplified code
Another small cleanup
Merge pull request #1112 from public/fix-docs

Fix syntax error in docs
Documentation and interfaces for serialization to RSA*Numbers representations.
This is a function, not a method
Merge pull request #1102 from reaperhulk/rsa-generate-function

add rsa_generate_private_key function to replace RSAPrivateKey.generate
Merge pull request #1107 from public/ecdsa-multibackend

ECDSA multibackend
Merge pull request #1113 from alex/small-cleanup

Another small cleanup
change names of key -> numbers interfaces
Merge pull request #1114 from alex/fixed-markup

This is a function, not a method