replace `incompatibility-graph` by `tig`
replace `incompatibility-graph` by `tig`

This was a misconception and should always have been `tig`.
For definition of the transitive incompatibility graph (`tig`), see https://arxiv.org/abs/1903.00686
For definition of the incompatibility graph (`incompatibility-graph`), see https://doi.org/10.1006/jagm.1998.0974

exot/conexp-clj,fcatools/conexp-clj,exot/conexp-clj,fcatools/conexp-clj,fcatools/conexp-clj,fcatools/conexp-clj,exot/conexp-clj,exot/conexp-clj,fcatools/conexp-clj,exot/conexp-clj