ENGINE_TABLE-based stuff - as described in crypto/engine/README.
Associated miscellaneous changes;
- the previous cipher/digest hooks that hardwired directly to EVP's
OBJ_NAME-based storage have been backed out. New cipher/digest support
has been constructed and will be committed shortly.
- each implementation defines its own ENGINE_load_<name> function now.
- the "openssl" ENGINE isn't needed or loaded any more.
- core (not algorithm or class specific) ENGINE code has been split into
multiple files to increase readability and decrease linker bloat.
- ENGINE_cpy() has been removed as it wasn't really a good idea in the
first place and now, because of registration issues, can't be
meaningfully defined any more.
- BN_MOD_EXP[_CRT] support is removed as per the README.
- a bug in enginetest.c has been fixed.
NB: This commit almost certainly breaks compilation until subsequent
changes are committed.
