ikev1: Use same map for AH and ESP authentication algorithms

The transform identifier used in AH transforms is not the same as the
authentication algorithm identifier used in the transform attributes in
AH (and ESP) transforms.
NEWS: Add note about AH algorithm mapping
Expanded bliss_bitpacker to 32 bits
unit-tests: added bliss_sampler test
Automatic generation of optimized Huffman codes
bliss: Fix compilation warning with certain GCC versions

Theoretically, n could be zero and these variables are then used
uninitialized.  Older GCC versions warn about this and on Travis where we
compile with -Werror this causes the tests to fail.
bliss: Fix monolithic build

This requires moving test files so that the Makefile for the tests can be
included after building libstrongswan, which requires the plugin when
building monolithically.  Due to this a static helper library is required
as directly referring to object files (or source files) is not possible.

It's also necessary to avoid any link-time dependency on libstrongswan in
bliss_huffman, to avoid circular dependencies (bliss_huffman -> libstrongswan
-> bliss -> bliss_huffman).