Disable harvesting of JVM metrics via ELASTICSEARCHATTRIBUTE=disabled for netvirt...

Disable harvesting of JVM metrics via ELASTICSEARCHATTRIBUTE=disabled for netvirt jobs.
The files set_elasticsearch_attribute.sh and set_jvm_common_attribute.sh which were removed from the repo integration/test were transformed into functions in jjb/integration/common-functions.sh

Minor fix - fixed Connection refused message.
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unix  3      [ ]         STREAM     CONNECTED     18101
ssh to karaf console to do bundle refresh of decanter jmx collector
ssh: connect to host localhost port 8101: Connection refused
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JIRA: INTTEST-63
Signed-off-by: Stanislav Chlebec <stanislav.chlebec@pantheon.tech>
Change-Id: If710cd4b19a988e941ebac2b0f129dbe7e15d473