NIFI-5468 add keypasswd with the default of keystorepasswd for bc compatibility
NIFI-5468 Use ARG instead of ENV for PATH variables as those need to be controlled in the build
NIFI-5468 Use BASE_URL for the default case when MIRROR_BASE_URL is not defined (and replace ARCHIVE_BASE_URL)
This closes#2921
Signed-off-by: Andrew I. Christianson <andy@andyic.org>
pepov