getos return Operating System name and version

## Syntax

                OS=getos()
                [OS,Version]=getos()

## Description

`[OS,Version]=getos()` returns Operating System name and version.

## Examples

    OS=getos()
    [OS,version] = getos()
    if (getos() == "Windows") then
       disp("Scilab on Windows");
    end
    if (getos() == "Linux") then
       disp("Scilab on Linux");
    end
    if (getos() == "SunOS") then
       disp("Scilab on Solaris");
    end
    if (getos() == "Darwin") then
       disp("Scilab on MacOs");
    end