Update CI for SLEEF

Add SLEEF support

Add SLEEF support. Seems pretty good

Remove unsupported libraries from tests

Tiny tweak

Fix Nyquist/DC bins in interleaved vDSP inverse

Minor tidy

Clarify this

No longer using Travis

Free these buffers

Tests and fixes for real inverse

Extended test case (currently failing)

Use clearer name

Merge tables and order according to index order

Further tidy

Tidy

Another lookup table

Further simplification of tables

We need to do this test more than once, otherwise the first case steals from the second

No longer so slow