sax parser filter generation generic logic

[vnitinv]

Handle below kind of YAML

twampProbeTable:
    rpc: twamp-get-probe-results
    item: probe-test-results
    key: test-name
    view: probeResultsView
probeResultsView:
    fields:
        min-delay: probe-test-global-results/probe-test-generic-results/probe-test-rtt/probe-summary-results/min-delay
        max-delay: probe-test-global-results/probe-test-generic-results/probe-test-rtt/probe-summary-results/max-delay
        avg-delay: probe-test-global-results/probe-test-generic-results/probe-test-rtt/probe-summary-results/avg-delay
        positive-rtt-jitter: probe-test-global-results/probe-test-generic-results/probe-test-positive-round-trip-jitter/probe-summary-results/avg-delay
        loss-percentage: probe-test-global-results/probe-test-generic-results/loss-percentage
        current-min-delay: probe-last-test-results/probe-test-generic-results/probe-test-rtt/probe-summary-results/min-delay
        current-max-delay: probe-last-test-results/probe-test-generic-results/probe-test-rtt/probe-summary-results/max-delay
        current-avg-delay: probe-last-test-results/probe-test-generic-results/probe-test-rtt/probe-summary-results/avg-delay
        current-positive-rtt-jitter: probe-last-test-results/probe-test-generic-results/probe-test-positive-round-trip-jitter/probe-summary-results/avg-delay
        current-loss-percentage: probe-last-test-results/probe-test-generic-results/loss-percentage

[coveralls]

Coverage increased (+0.1%) to 91.474% when pulling d73843d on vnitinv:sax-parser-filter into 3584916 on Juniper:master.