function cleardvalue(obj) {
    obj.value = "";
}
function replacedvalue(obj) {
    obj.value = "Please enter a keyword";
}
function replacelvalue(obj) {
    obj.value = "e.g London";
}
function replacefvalue(obj) {
    obj.value = "From";
}
function replacetvalue(obj) {
    obj.value = "To";
}