Extended Ranges

See:

• http://www.eda-twiki.org/cgi-bin/view.cgi/P1076/ExtendedRanges,
• http://www.eda-twiki.org/cgi-bin/view.cgi/P1076/LCS2016_099 and
• http://www.eda-twiki.org/cgi-bin/view.cgi/P1076/TopLCS2016_099a.

LCS2016-099 ⇒ Make ranges more powerful VHDL: '19
LCS2016-099a ⇒ Locally static Missed: VHDL'19

So the remaining problem is to care about locally static for user defined operators.