PR# 20018 Large inspect interval

The following code:

```eiffel
	inspect i
	when 1 .. 1_000_000_000 then
		...
	else
		...
	end
```

will generate a 20 GB C file and the C compiler will fail to compile it ("compiler is out of heap space").

Solution adopted in Gobo Eiffel compiler: detect such huge intervals and generate `if ... else if ...` statements instead of `switch .. case ...` statements in these cases.

--
Eric Bezault