Add graphics widget macros

[abigailalexander]

Phoebus now longer has a pv_name field on Graphics widgets Arc, Ellipse, Image, Label, Polyline, Polygon and Rectangle. This has been replaced by a macros field, which can be used to specify pv_name or other fields (if needed for rules such as changing background colour). I've added the macros field into these widgets, and also ensured these macros get parsed with the others.

I tested this with some widgets that looked like this:

<widget type="rectangle" version="2.0.0">
    <name>EDM Rectangle</name>
    <macros>
      <pv_name>PV NAME HERE</pv_name>
    </macros>
    <width>50</width>
    <height>50</height>
    <line_width>0</line_width>
    <line_color>
      <color name="Black" red="0" green="0" blue="0">
      </color>
    </line_color>
    <background_color>
      <color red="0" green="224" blue="0">
      </color>
    </background_color>
    <rules>
      <rule name="background_color_machineStatusRule" prop_id="background_color" out_exp="false">
        <exp bool_exp="pv0== 1">
          <value>
            <color red="0" green="224" blue="0">
            </color>
          </value>
        </exp>
        <exp bool_exp="true">
          <value>
            <color red="255" green="0" blue="0">
            </color>
          </value>
        </exp>
        <pv_name>$(pv_name)</pv_name>
      </rule>
    </rules>
  </widget>

To ensure the macro was passed to the rules

[rjwills28]

I've tested this with a screen created with Phoebus containing some of the example widgets listed and all looks good 👍 . Verified the reported issue and associated fix.