packaging: spec: always pull recent pythonlib

Related-To: https://bugzilla.redhat.com/show_bug.cgi?id=1009863
Change-Id: I113dd0a5bb477b02d857dcca820fd2a2a8b54762
Signed-off-by: Alon Bar-Lev <alonbl@redhat.com>
packaging: detect java home at runtime

CURRENT IMPLEMENTATION

detect java home during installation.

advantage is optimize application execution post-setup.

disadvantage is that java home may be altered by system updates.

NEW IMPLEMENTATION

detect java home during runtime using pre-defined algorithm.

algorithm:

execute /usr/share/ovirt-engine/bin/java-home.

if java-home.local is available, execute that script. this enables
distro specific customization.

if OVIRT_ENGINE_JAVA_HOME environment is set, validate java validity
and use/abort.

search predefined selected alternatives location by order, first wins.

search /usr/lib/jvm for compatible jvm.

NOTES

the java-home script resides with the lib package as it cannot reside
within any version locked package since it is used by setup, and it
cannot reside within setup since it used by post setup.

Bug-Url: https://bugzilla.redhat.com/show_bug.cgi?id=1009863
Change-Id: I833362d0498d534b06e0d7660f1e8a61e9b1713b
Signed-off-by: Alon Bar-Lev <alonbl@redhat.com>