Legacy behavior for INI read int/float when value does not contain number

[MiranDMC]

Commands read_int_from_ini_file and read_float_from_ini_file called from scripts in legacy mode now returns success and value 0 in case of invalid data inside ini file.
Fixes #281

Test script.

{$CLEO .cs}

//set_current_directory 1

write_int_to_ini_file {value} 42 {path} "test.ini" {section} "t" {key} "iVal"
write_float_to_ini_file {value} 42.0 {path} "test.ini" {section} "t" {key} "fVal"
//write_string_to_ini_file {value} "forty two" {path} "test.ini" {section} "t" {key} "sVal" // CLEO4 crash

while true
    wait 100
    
    int iVal = 123
    int iResult = false
    if
        iVal = read_int_from_ini_file {path} "test.ini" {section} "t" {key} "iVal"
    then
        iResult = true
    end
    
    float fVal = 123
    int fResult = false
    if
        fVal = read_float_from_ini_file {path} "test.ini" {section} "t" {key} "fVal"
    then
        fResult = true
    end
    
    longString sVal = "default"
    int sResult = false
    if
        sVal = read_string_from_ini_file {path} "test.ini" {section} "t" {key} "sVal"
    then
        sResult = true
    end
    
    print_formatted_now {format} "INT - ok: %d, value: %d~n~FLOAT - ok: %d, value: %f~n~TXT - ok: %d, value: %s" {time} 1000 {args} iResult iVal fResult fVal sResult sVal
end