feature request: metric for fan rpms

[christianpinger]

Metrics for fan rpms would be very helpful

example output

Device (e.g. MX, QFX and SRX)

user@mx-router> show chassis fan | display xml
<rpc-reply xmlns:junos="http://xml.juniper.net/junos/XXX/junos">
    <fan-information xmlns="http://xml.juniper.net/junos/XXX/junos-chassis" junos:style="rpm">
        <fan-information-rpm-item>
            <name>Top Tray Fan 1</name>
            <status>OK</status>
            <rpm>3218</rpm>
            <comment>Spinning at normal speed</comment>
        </fan-information-rpm-item>
        <fan-information-rpm-item>
            <name>Top Tray Fan 2</name>
            <status>OK</status>
            <rpm>3239</rpm>
            <comment>Spinning at normal speed</comment>
        </fan-information-rpm-item>
        <fan-information-rpm-item>
            <name>Top Tray Fan 3</name>
            <status>OK</status>
            <rpm>3239</rpm>
            <comment>Spinning at normal speed</comment>
        </fan-information-rpm-item>
...
        <fan-information-rpm-item>
            <name>Bottom Tray Fan 12</name>
            <status>OK</status>
            <rpm>3218</rpm>
            <comment>Spinning at normal speed</comment>
        </fan-information-rpm-item>
    </fan-information>
    <cli>
        <banner>{master}</banner>
    </cli>
</rpc-reply>

Satellite-Device

user@mx-router> show chassis fan satellite | display xml
<rpc-reply xmlns:junos="http://xml.juniper.net/junos/XXX/junos">
    <fan-information xmlns="http://xml.juniper.net/junos/XXX/junos-chassis" junos:style="rpm">
        <fan-information-rpm-item>
            <name>FPC 102 Tray 0 Fan 0</name>
            <status>OK</status>
            <rpm>5400</rpm>
            <comment>Spinning at normal speed</comment>
        </fan-information-rpm-item>
        <fan-information-rpm-item>
            <name>FPC 102 Tray 1 Fan 0</name>
            <status>OK</status>
            <rpm>5263</rpm>
            <comment>Spinning at normal speed</comment>
        </fan-information-rpm-item>
        <fan-information-rpm-item>
            <name>FPC 102 Tray 2 Fan 0</name>
            <status>OK</status>
            <rpm>5341</rpm>
            <comment>Spinning at normal speed</comment>
        </fan-information-rpm-item>
    </fan-information>
    <cli>
        <banner>{master}</banner>
    </cli>
</rpc-reply>