Log matching discovered toolchain as info in select-jdk-toolchain mojo

[HannesWell]

Fixes #141

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[slawekjaranowski]

Maybe this should be in info level as it is final decision

[HannesWell]

I think printing the final decision makes sense.
But with what's now all info I believe it might be a little bit too verbose for the standard log level case.
My suggestion would be to either have this an info or

• maven-toolchains-plugin/src/main/java/org/apache/maven/plugins/toolchain/jdk/SelectJdkToolchainMojo.java

  Line 198 in df2ecab

  getLog().info("Found matching JDK toolchain: " + toolchain);

• maven-toolchains-plugin/src/main/java/org/apache/maven/plugins/toolchain/jdk/SelectJdkToolchainMojo.java

  Line 210 in df2ecab

  getLog().debug("Discovered matching JDK toolchain: " + toolchain);

What I like about the latter two is that one can derive from the printout the origin of the toolchain.
On the other hand, the former is more clear that it's the final decision (especially after I've adjusted the printout a bit).
To get the best from both world, we could add a variable that captures the origin and prints it as part of the final decision message.

[slawekjaranowski]

This one is also information about final decision

[HannesWell]

Yes, this should be an info too especially as it 'diverts' from what one would expect from the preceding printout.