Update lf-maven-stage macro with missing parts

Update lf-maven-stage macro with missing parts

Added the following missing parts to the lf-maven-stage macro.

* lf-provide-maven-settings
* lf-infra-create-netrc
* lf-provide-maven-settings-cleanup

This improves the macro to be a complete function that does not require
preparatory steps to complete it.

New Usage:

      - lf-maven-stage:
          mvn-global-settings: 'global-settings'
          mvn-settings: 'settings'
          mvn-staging-id: 'staging-profile-id'

This patch also updates the lf-maven-central macro as necessary to
work along side the lf-maven-stage changes.

Issue: RELENG-1554
Change-Id: Ie4fbcb52229c74c4216df4d07f077cd691ab6aa6
Signed-off-by: Bengt Thuree <bthuree@linuxfoundation.org>