Add property: ℵ₁-cofiltered limits

[ScriptRaccoon]

This PR adds two properties (whose duals are already in the database):

• being $\aleph_1$-cofiltered
• having $\aleph_1$-cofiltered limits

This has been motivated by deciding some existing properties in the database (such as being coaccessible). For the deduction system to properly work, properties should also always be dualized.

Surprisingly, $\aleph_1$-cofiltered limit exist in many cases, even when cofiltered limits do not exist. The situation is similar to the $\aleph_1$-filtered colimits (#179).

For the following two categories, having $\aleph_1$-cofiltered limits could not be decided:

• FreeAb
• Sch

Next step: add the property $\aleph_1$-coaccessible (we already have $\aleph_1$-accessible in the database).

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• unknown (category, property)-pairs before this PR: 115
• unknown (category, property)-pairs before this PR: 117 😕