Allow using WagonTransporter (or configure aether)

[ca-stefan-cordes]

By default the mule-maven-plugin is using aether-transport-http but that cannot be configured via settings.xml
with .m2/settings.xml//servers/server/configuration/httpConfiguration
(see references to org.eclipse.aether.transport.http.GlobalState.setExpectContinue(CompoundKey, boolean) and org.eclipse.aether.transport.http.HttpTransporterFactory)

What we need is for example a configuration for our nexus: preemptive + http-continue:

<configuration>
	<httpConfiguration>
		<all>
			<params>
				<property>
					<name>http.authentication.preemptive</name>
					<value>%b,true</value>
				</property>
				<property>
					<name>http.protocol.expect-continue</name>
					<value>%b,false</value>
				</property>
			</params>
		</all>
	</httpConfiguration>
</configuration>

and that can be achieved with wagon transport only.

Workaround is to exclude the aether-transport-http from mule-maven-client-impl

<pluginManagement>
	<plugins>
		<plugin>
			<groupId>org.mule.tools.maven</groupId>
			<artifactId>mule-maven-plugin</artifactId>
			<dependencies>
				<dependency>
					<groupId>org.mule</groupId>
					<artifactId>mule-maven-client-impl</artifactId>
					<version>${mule-maven-client-impl.version}</version>
					<exclusions>
						<exclusion>
							<groupId>org.eclipse.aether</groupId>
							<artifactId>aether-transport-http</artifactId>
						</exclusion>
					</exclusions>
				</dependency>
			</dependencies>
		</plugin>
	</plugins>
</pluginManagement>