Backport testsuite and travis-ci support to 1.1.0 branch 

grasshopper-omac is not implemented in this version of engine.

(cherry picked from commit 234823a6)

(cherry picked from commit 641223f4)

openssl-1.1.0 made ctx opaque and does not allow it on stack anymore.

(cherry picked from commit 20e590a4)

(cherry picked from commit a53589ac)

Encrypt with small chunks to verify that internal state is handled
correctly between calls.

(cherry picked from commit 3b130109)

These tests are with generated test vectors from canonical TC26
implementation with truncated IVs.

(cherry picked from commit 9c0f7cd7)

(cherry picked from commit ee15414b)

Full test of OFB to match GOST R 34.13-2015 test vectors is impossible,
due to test IVs are having size (256-bits) over the maximum openssl can
allow (128-bits).

I generated new test vectors from canonical implementation
from `PR_GOSTR_bch_v9.zip` (revision of 2016-10-28) by truncating test
IVs in half.

(cherry picked from commit d40efde8)

Make sure stream modes can encrypt any block size.

(cherry picked from commit 6e163b2c)

(cherry picked from commit 370c40df)

test_grasshopper: test modes to match GOST vectors
Only ECB and CTR modes are tested. OBF, CBC, CFB modes is not testable
under openssl.

(cherry picked from commit 6547c44e)

Co-authored-by: Mikhail Gordeev <obirvalger@altlinux.org>
(cherry picked from commit 0329b9a7)

(*) convert 'openssl ciphers | grep ...' into Test:More syntax

(cherry picked from commit abf1f767)

(cherry picked from commit 1d378c56)

(cherry picked from commit 6eb11c67)

(cherry picked from commit 3461793c)

Backport grasshopper-ctr and grasshopper-ofb fixes to 1.1.0 branch

Also, document why CTR IV size is now set to 16, so user is noted to set
IV appropriately to full extent (including counter). Basically, it's for
openssh (and alike) to make it copy IV from privilege separated process.

(cherry picked from commit 74d13288)

Previous implementation was not OFB at all, and fail tests.

Note: This implementation is for fixed width 128-bit IV which makes
shift regiser redundant.

(cherry picked from commit 1e15537d)

Previously CTR did not continue unfinished block on the next cipher
iteration.

(cherry picked from commit cf2ab51a)

(cherry picked from commit 6be1ab00)

Address compiler warnings and build with CMAKE_C_FLAGS

like the README suggests.