Support single quote XML Attributes

[eisenwr]

It would be helpful if the Pretty XML to Tree Map supported attributes entered in single quotes. The LabVIEW XML parser supports this format and NI uses it in some TestStand configuration files. See an example below.

Example XML:

<?xml version="1.0" encoding="UTF-8"?>
<teststandfileheader type='GeneralEngineConfigFile' fileversion='920' productname='TestStand' productversion='2019 (19.0.0.170)' compatibleversion='19.0.0.0' buildversion='19.0.0.170' xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.ni.com/TestStand/19.0.0/PropertyObjectFile">
	<typelist>
		<typedef alwayssavetype='false' additionaltypeflags='0' typelistordernum='0'>
			<Path classname='PathValue' isroottypedef='true' typecategory='3' timestamp='1567615663' typeversion='19.0.0.170' typelastmodversion='19.0.0.170' typeminprodversion='19.0.0.0' typeflags='33554436'>
				<value/>
			</Path>
		</typedef>
		<typedef alwayssavetype='false' additionaltypeflags='0' typelistordernum='1'>
			<Expression classname='ExprValue' isroottypedef='true' typecategory='3' timestamp='1567615663' typeversion='19.0.0.170' typelastmodversion='19.0.0.170' typeminprodversion='19.0.0.0' typeflags='33554436'>
				<value/>
			</Expression>
		</typedef>
	</typelist>

[SoftwareMinimalist]

This is a great idea and should be quite straightforward to implement. I'm putting it in the plan for next version.