Add maven download and publish commands

[noamkfir]

• Support fetching optional dependencies, which are not returned by dependency:resolve. Transitive dependencies can be fetched with mvn dependency:tree.
• Support fetching sources.
• Support fetching javadocs.
• Support publishing with mvn deploy despite expired certificates: Dmaven.wagon.http.ssl.insecure=true, and possibly Dmaven.wagon.http.ssl.allowall=true and Dmaven.wagon.http.ssl.ignore.dates=true