List of deprecate types to be removed

[unional]

To remove:

• First (FindFirst, ArrayPlus.Find)
• isType.t() (isType(), testType.true())
• isType.f() (isType(), testType.false())
• isType.never() (isType(), testType.never())
• isType.equal() (testType.equal())
• CommonKeys (CommonPropKeys)
• PadLeft (PadStart)

Newly deprecated:

• drop() (no replacement)
• Concat (ArrayPlus.Concat)