Submitted by: Lenka Fibikova

use BN_CTX_start/get/end instead of accessing ctx->tos).

Change indentation to "EAY" style.

These new files will not be included literally in OpenSSL, but I intend
to integrate most of their contents.  Most file names will change,
and when the integration is done, the superfluous files will be deleted.

Submitted by: Lenka Fibikova <fibikova@exp-math.uni-essen.de>