Use jbosstools_site_update in Jenkins jobs and jbosstools-site-update in parent pom for "consistency" & "less confusion"

Max wants that:

• the parameter we use in Jenkins be jbosstools_site_stream (underscores) and that

• the maven processes all use jbosstools-site-stream (dashes)

Because

• Max feels that using a different parameter in Jenkins than the value in the parent pom is more consistent & less likely to cause problems, vs.

• renaming the variable so that both use the same underscored name of jbosstools_stream.