Cleaning up JenkinsBuildInvocation
Renaming and cleaning up TestJenkinsBuildInvocation
Cleaning up synthetic.xml
Renaming BuildJob -> RunBuild
Cleaning up BuildJob.py
Avoiding an NPE if the optional property 'parameters' is empty
Using a 'neater' version of cli.authenticate
Renaming packages based on review feedback

c.x.xlrelease.plugins.ci.jenkins -> c.x.xlrelease.plugin.jenkins
Supporting unsecured key files
Supporting unsecured Jenkins installations
Additional comments explaining the CLI build command
Ensuring the CLI connection is closed even if an error occurs
Removing cli.upgrade() as it's not needed