etl

Make tests build with C++14

#627

Merged

Specify array size for bit_stream so C++14 works.

Change send message call. (build error in c++14 since unhandled)

Update murmur3 test for C++14.

Fix unaligned_type to work with C++14.

Disable unsupported type_traits checks in C++14.

Get variant_variadic tests in C++14.

Get type_lookup tests working in C++14.

Get poly_span tests working in C++14.

Get span tests working in C++14.

Bitset and instance_count

Largest working in C++14 tests.

Parameter pack working in C++14 with limited support.

Make constants by using enums.

Disable tests for string utilities for standard library on C++14.

Disable C++17 check and remove warning for function signature change between C++14 and 17. The warning doesn't matter, since it's not dynamically linked.

Set standard to C++17

Set default to C++17, but allow it to be changed from the command line.

Add C++14 builds.

Give C++14 builds a distinguishing name.

Fix undefined variables with No-STL.

Fix message_packet unused parameter warning.

Fix clang warning regarding `typename` being a C++17 extension. Tests still pass with it being changed to `class`.

Add copy constructors for reference wrappers, since when manually creating an assignment operator, the copy constructor is not automatically created.

Change to requiring C++14 or newer support for tests.

Build with the total number of cores available.

* Add an `ETL_OR_STD17` define and use it for `size`.

Merge branch 'feature/#627-Make-tests-build-with-C++14' into master