Added Khmer language

[melloware]

This is fantastic @chhaihong-dev ! Any change I could get some extra translations here for PrimeFaces?

 {
    weekNumberTitle: "W",
    isRTL: false,
    yearSuffix: "",
    timeOnlyTitle: "Only Time",
    timeText: "Time",
    hourText: "Hour",
    minuteText: "Minute",
    secondText: "Second",
    millisecondText: "Millisecond",
    year: "Year",
    month: "Month",
    week: "Week",
    day: "Day",
    list: "Agenda",
    allDayText: "All Day",
    moreLinkText: "More...",
    noEventsText: "No Events",
    unexpectedError: "Unexpected error",
    aria: {
      "datatable.sort.ASC": "activate to sort column ascending",
      "datatable.sort.DESC": "activate to sort column descending",
      "datatable.sort.NONE": "activate to remove sorting on column",
      "colorpicker.OPEN": "Open color picker",
      "colorpicker.CLOSE": "Close color picker",
      "colorpicker.CLEAR": "Clear the selected color",
      "colorpicker.MARKER": "Saturation: {s}. Brightness: {v}.",
      "colorpicker.HUESLIDER": "Hue slider",
      "colorpicker.ALPHASLIDER": "Opacity slider",
      "colorpicker.INPUT": "Color value field",
      "colorpicker.FORMAT": "Color format",
      "colorpicker.SWATCH": "Color swatch",
      "colorpicker.INSTRUCTION": "Saturation and brightness selector. Use up, down, left and right arrow keys to select.",
      "spinner.INCREASE": "Increase Value",
      "spinner.DECREASE": "Decrease Value",
      "switch.ON": "On",
      "switch.OFF": "Off",
      "messages.ERROR": "Error",
      "messages.FATAL": "Fatal",
      "messages.INFO": "Information",
      "messages.WARN": "Warning",
    },

You can just paste the response here if you want!