Add some missing PWN 3.1 ILI maps

[jmccrae]

As discussed in #16 some of the mappings that are reported as changed in PWN 3.1 are in fact not and have ILI codes. This PR fixes this by putting back all the matching synsets with the correct ILI

[fcbond]

This has several mappings from one ili to multiple synsets, which is not allowed:

• we should probably try to add an automated test for this
• a simple one-liner for the tab file is

$ sort ili-map-pwn31.tab | cut -f 1 | uniq -d
i10616
i114673
i114674
i114676
i114677
i114679
i114680
i16842
i25156
i34688
i3764
i4234
i4304
i55794
i55822
i56320
i56630

I think we should also check the ili.ttl file as well.

[jmccrae]

I updated the branch so it has no duplicates and ILI to PWN 3.1 mappings are correct