FIX #1177614. Clarify that RSA OAEP only works on byte strings
Clarify that PKCS#1v1.5 encryption only works on byte strings
Add table to Crypto.Util package docs
FIX #1093446. Description of allow_wraparound was incorrect.

In addition to fixing the problem, the patch also
improves readibility of other sentences a little.
FIX #1096857. Update reference to FIPS 180-4.
Clarify that padding is ignored by Cipher classes

This small patch clarifies that encrypt()
and decrypt() do not respectively add and remove
any padding.
Undocumented Counter parameter: overflow

This small patch documents what the 'overflow' parameter
does (that is, nothing) to the Counter class.