Gradle: create maven artifacts

[planetf1]

Description

• Adds publishing of all maven artifacts . For example, for a local ~/.m2 publish use:

./gradlew build publishToMavenLocal

Publishing to official repos is coded, but not yet tested as it can only run in the CI/CD process.

The relevant Java 'jar', as well as javadoc & sources (required for maven central) are included.

• Refactors gradle file for legibility

Related Issue(s)

See #3370

Testing

For this first stage, I've only verified artifacts are created. Their names default to the directory name - this needs checking against maven, as do their contents

ie After a local publish, output can be found in ~/.m2/repository/org/odpi/egeria

➜  v4 git:(gradle40) ls -latr ~/.m2/repository/org/odpi/egeria/graph-repository-connector
total 8
drwxr-xr-x  424 jonesn  staff  13568 18 Oct 17:25 ..
drwxr-xr-x    8 jonesn  staff    256 18 Oct 17:25 3.13-SNAPSHOT
drwxr-xr-x    4 jonesn  staff    128 18 Oct 17:25 .
-rw-r--r--    1 jonesn  staff    335 18 Oct 18:38 maven-metadata-local.xml
➜  v4 git:(gradle40) ls -latr ~/.m2/repository/org/odpi/egeria/graph-repository-connector/3.13-SNAPSHOT
total 1144
drwxr-xr-x  8 jonesn  staff     256 18 Oct 17:25 .
drwxr-xr-x  4 jonesn  staff     128 18 Oct 17:25 ..
-rw-r--r--  1 jonesn  staff    1298 18 Oct 18:38 maven-metadata-local.xml
-rw-r--r--  1 jonesn  staff  140058 18 Oct 18:38 graph-repository-connector-3.13-SNAPSHOT.jar
-rw-r--r--  1 jonesn  staff   26070 18 Oct 18:38 graph-repository-connector-3.13-SNAPSHOT.pom
-rw-r--r--  1 jonesn  staff   28005 18 Oct 18:38 graph-repository-connector-3.13-SNAPSHOT.module
-rw-r--r--  1 jonesn  staff  105601 18 Oct 18:38 graph-repository-connector-3.13-SNAPSHOT-sources.jar
-rw-r--r--  1 jonesn  staff  189786 18 Oct 18:38 graph-repository-connector-3.13-SNAPSHOT-javadoc.jar

• Still need to verify javadoc build ok
  a) aggregate - this is published, and is a subset of our javadoc but in a single report. Patterns are specified in the build.gradle to fine tune the contents.
  b) module - this is uploaded to maven central, and is mandatory for every module, and should have content.

Release Notes & Documentation

Additional notes

• Maven artifacts still need checking. This is prep work for v4 and not used for any release activity yet
• Most of our 'packaging' poms are not created. They have no build.gradle (intentionally) - this needs review.

[planetf1]

Testing notes:

The only warning produced is:

Multiple publications with coordinates 'org.odpi.egeria:glossary-author-fvt:3.13-SNAPSHOT' 
are published to repository 'mavenLocal'. The publications 'connector' in project 
':open-metadata-test:open-metadata-fvt:access-services-fvt:glossary-author-fvt' and 
'connector' in project 
':open-metadata-test:open-metadata-fvt:view-services-fvt:glossary-author-fvt' 
will overwrite each other!

[planetf1]

This initial update to create maven artifacts will be merged - issue #3370 has more notes on some of the next steps
on maven artifacts to bring the build closer to maven parity