Add Arch Linux support

[cartok]

Add Arch Linux support

On my Arch Linux, the script did not work, did not detect JAVA_HOME.

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[lbruun]

If user has already set the JAVA_HOME then this code will not take that into account. In other words, the step need to surrounded by:

if [ -z "$JAVA_HOME" ]; then

fi

Also, it may be worthwhile to explain why existing code does not work with Arch Linux. What is it that makes Arch Linux special, compared to any other Linux?

[gnodet]

This should definitely be already covered by:

https://github.com/apache/maven-wrapper/blob/88e83587f83a8b8c72d50ea419236923774b15db/maven-wrapper-distribution/src/resources/mvnw#L106-L124

Please reopen if needed.