Controls the look for linear gauges.
Example:
<linear orientation="horizontal">
<axis size="50">
<scale minimum="0" maximum="100" major_interval="10" minor_interval="2" />
<labels enabled="true">
<font bold="true" />
<format>{%Value}{numDecimals:0}</format>
</labels>
<minor_tickmark enabled="false" />
<color_ranges>
<color_range start="0" end="30" color="Red">
<label>
<format>Bad</format>
</label>
</color_range>
<color_range start="30" end="65" color="Yellow">
<label>
<format>Good</format>
</label>
</color_range>
<color_range start="65" end="100" color="Green">
<label>
<format>Excellent</format>
</label>
</color_range>
</color_ranges>
<custom_labels>
<custom_label value="65" enabled="true">
<label align="Outside" enabled="true" padding="20">
<format>Planned</format>
</label>
<tickmark enabled="true" shape="Star5" width="20" length="20" align="Outside" padding="10">
<fill color="Yellow" />
<border color="DarkColor(Yellow)" />
</tickmark>
</custom_label>
</custom_labels>
</axis>
<frame enabled="true">
<background enabled="true">
<border enabled="true" color="Black" />
</background>
</frame>
</linear>