Added Maven dependency example

[clehene]

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[clehene]

I signed the CLA

[googlebot]

CLAs look good, thanks!

[nick-someone]

Can you please describe in what circumstances one would want to add the explicit dependency on log4j/exclusions? If I'm reading this directly, I don't know why/when I would do this instead of the first example above.

If the explanation is long enough, perhaps a footnote would help?

[clehene]

@nglorioso I don't know / remember. Flogger wasted more time than it saved to the point where we ended up debugging JUL in tears.

It manages to take something that typically causes problems (e.g. slf4j + X) and compounds that complexity into something more difficult. I'm not sure it's worth the trouble.

I may be too stupid / ignorant to actually figure it out. Currently have to do static blocks like

  static {
    System.setProperty("flogger.backend_factory", "com.google.common.flogger.backend.slf4j.Slf4jBackendFactory#getInstance");
  }

to get it working but for some reason this PR is still open...

Here's how the dependency management section looks like

      <dependency>
        <groupId>com.google.flogger</groupId>
        <artifactId>flogger</artifactId>
        <version>${google.flogger.version}</version>
      </dependency>
      <dependency>
        <groupId>com.google.flogger</groupId>
        <artifactId>flogger-system-backend</artifactId>
        <version>${google.flogger.version}</version>
        <scope>runtime</scope>
      </dependency>
      <dependency>
        <groupId>com.google.flogger</groupId>
        <artifactId>flogger-slf4j-backend</artifactId>
        <version>${google.flogger.version}</version>
      </dependency>
      <dependency>
        <groupId>org.slf4j</groupId>
        <artifactId>slf4j-api</artifactId>
        <version>${slf4j.version}</version>
      </dependency>
      <dependency>
        <groupId>ch.qos.logback</groupId>
        <artifactId>logback-classic</artifactId>
        <version>${logback.version}</version>
      </dependency>
      <dependency>
        <groupId>ch.qos.logback</groupId>
        <artifactId>logback-core</artifactId>
        <version>${logback.version}</version>
      </dependency>

[nick-someone]

It might be helpful to move the NOTE from below to above the Maven subheading and add inline XML comments like:

<!-- only in root component of your application --> 

above flogger-log4j-backend