run under cargo miri

[folkertdev]

On x86, we need the pclmulqdq and the crc32 instructions. There are now PRs for both

• add support for pclmulqdq intrinsic rust-lang/miri#3640
• Implement LLVM x86 SSE4.2 intrinsics rust-lang/miri#3622

here is the current list of tests that fail in zlib-rs itself (libz-rs-sys uses libz-sys a bunch so there is no point to run miri on them).

most of these now use libz-sys which we should try to get rid of over time (and move such tests into libz-rs-sys if possible).

     Summary [ 562.330s] 66 tests run: 41 passed (19 slow), 25 failed, 0 skipped
   FAIL [ 198.125s] zlib-rs deflate::test::block_flush
        FAIL [   6.768s] zlib-rs deflate::test::compress_fireworks
        FAIL [   6.381s] zlib-rs deflate::test::compress_lcet10
        FAIL [   6.141s] zlib-rs deflate::test::compress_paper_100k
        FAIL [ 191.198s] zlib-rs deflate::test::copy_invalid_allocator
        FAIL [   6.272s] zlib-rs deflate::test::fill_window_out_of_bounds
        FAIL [ 310.667s] zlib-rs deflate::test::full_flush
        FAIL [   7.260s] zlib-rs deflate::test::gzip_no_header
        FAIL [   6.245s] zlib-rs deflate::test::gzip_stored_block_checksum
        FAIL [ 210.712s] zlib-rs deflate::test::gzip_with_header
        FAIL [ 168.705s] zlib-rs deflate::test::partial_flush
        FAIL [   7.712s] zlib-rs deflate::test::read_buf_window_uninitialized
        FAIL [   6.963s] zlib-rs deflate::test::rs_is_ng
        FAIL [   7.059s] zlib-rs deflate::test::simple_rle
        FAIL [ 162.159s] zlib-rs deflate::test::sync_flush
        FAIL [ 152.729s] zlib-rs deflate::test::test_reset_keep
        FAIL [   7.744s] zlib-rs deflate::test::zlib_ng_cve_2018_25032_default
        FAIL [   7.517s] zlib-rs deflate::test::zlib_ng_cve_2018_25032_fixed
        FAIL [   6.671s] zlib-rs deflate::test::zlib_ng_gh_382