Adding arccot, arcsec and arccsc for bug 35186.
Adding arccot, arcsec and arccsc for bug 35186.

This says to treat these commands as Named functions, just as arcsin, arctan etc.

Change-Id: Ib11d9cb99f4ced0a063fd0913b9cacf544049f36

physikerwelt/mathoid-server,MonashAlexandria/mathoid,physikerwelt/mathoid-server,wikimedia/mathoid,kwangkim/mathoid,wikimedia/mathoid,MonashAlexandria/mathoid,kwangkim/mathoid,wikimedia/mathoid,kwangkim/mathoid,physikerwelt/mathoid-server,kwangkim/mathoid,wikimedia/mathoid