Change the default logger from java.util.logging to SLF4J

[backpaper0]

Impact on users

• Users who were using the default setting (JUL):
  • It will be switched to SLF4J.
  • If they wish to continue using JUL, they will need to add explicit configuration.

    doma.jdbc-logger=JUL
    
• Users who were explicitly using JUL:
  • org.seasar.doma:doma-slf4j will be included as a dependency.
  • To exclude it, they need to explicitly add an exclusion in pom.xml:

    <dependency>
        <groupId>org.seasar.doma</groupId>
        <artifactId>doma-spring-boot</artifactId>
        <version>x.y.z</version>
        <exclusions>
            <exclusion>
                <groupId>org.seasar.doma</groupId>
                <artifactId>doma-slf4j</artifactId>
            </exclusion>
        </exclusions>
    </dependency>
• Users who were using SLF4J:
  • No impact.
  • Explicit configuration is no longer necessary.

Related Issue

closes gh-287

Others

The "Configuration" page on the wiki needs to be updated.