Added check to turn of CC backend for OS X version < 10.8
Fix drop in coverage levels by removing branches
Removed dependency on setuptools for version check
Fixed python3 incompatibility
Merge pull request #744 from Ayrx/osx-version-check

Added check to turn off CC backend for OS X version < 10.8
Added note in documentation about OS X version support
Added future imports and licenses that are missing
flake8
Merge pull request #760 from Ayrx/add-supported-osx-version-to-docs

Added note in documentation about OS X version support
Merge pull request #761 from alex/missing-future-license

Added future imports and licenses that are missing
Various "improvements" to the symmetric docs
Update HMAC and Digest docs.
Merge pull request #766 from public/more-doc-tweaks

Various "improvements" to the symmetric docs
Merge pull request #765 from public/doc-tweaks

Update HMAC and Digest docs.
document our oldest supported openssl and deny older support
add two RSA items we need for PSS
add mgf1_hash_supported to the RSABackend interface
Merge pull request #770 from reaperhulk/document-some-versions

Document our oldest supported openssl and deny older support
Merge pull request #771 from reaperhulk/rsa-err-symbols

Add two RSA items we need for PSS
Merge pull request #772 from reaperhulk/rsa-mgf1-supported-interface

Add mgf1_hash_supported to the RSABackend interface