Package release v1.0.6

[urfeex]

Since releasing 1.0.5 (5 years ago!) we had two bugfixes coming in, namely #38 and #40.

Let's release a new version including those fixes.

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Note

Low Risk
Only the POM version string changes; no application or build-plugin logic is modified in this diff.

Overview
Bumps the Maven project version in pom.xml from 1.0.5 to 1.0.6 for the External Control URCap (com.fzi:externalcontrol).

That version drives ${project.build.finalName} for the built JAR and .urcap package produced at the package phase, aligning the release artifact with v1.0.6 (including prior bugfixes referenced in the PR description).

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[urfeex]

Before making the actual release, I think I would want to wait until UniversalRobots/Universal_Robots_Client_Library#543 is released to all active ROS distributions (Which is version >= 2.14.1).

[urfeex]

URCL is now available as 2.15.0 or higher in all ROS distros' main channel.