[#179] Rename `Rec`-based expressions from Indigo and solve their inconsistent names

Description

Problem: construct, entryCase and case_ namings are inconsistent. They also have tuple version, adding the suffix -T. However the tuple version is more commonly used.

Solution: Rename the current construct, entryCase and case_ adding suffix -Rec instead. Rename the old tuple version, using simplest name instead.

Related issue(s)

Resolves #179 (closed)

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