Doc: Describe proper use of long values in expressions

[psmf22]

The documentation currently does not describe how to properly filter on long values.
Using the syntax described for numeric values leads to the following error:

.\fcli.exe util sample-data list -q "longValue==9223372036854775807"
Invalid value for option '--query': Expression cannot be parsed; please check expression syntax
Message: EL1035E: The value '9223372036854775807' cannot be parsed as an int
Source: longValue==9223372036854775807

This seems to be caused by numbers being treated as integers by default. To achieve a proper comparison the number has to be followed by the letter "L". Both uppercase and lowercase notations work.

Working example:

.\fcli.exe util sample-data list -q "longValue==9223372036854775807L"

[rsenden]

I'd suggest documenting only the upper-case L variation as it's more common and easier to recognize; with some fonts, a lowercase l could be easily confused with a 1 (or I, even though that has no meaning here, except maybe for explicitly identifying an Integer)