Improve RpcProviderRegistry loading

Profiling monitor usage at startup has shown that we spend about 19s of
CPU time over ~50 second bootup waiting in getRpcService(). Instead of a
home-grown cache, let's use a guava Loading cache, which allows us to
concurrently instantiate multiple rpc services at the same time.

Change-Id: Ieaaedd7da61cd0b03b05a44ee2a6285bc8eb46ac
Signed-off-by: Robert Varga <rovarga@cisco.com>
Bug-1376 Add caching for premature notifications in netconf connector

If a notification is received before schema context is fully built for device, it is cached and forwarded when schema is present.

Change-Id: Ib21fc0fab9cf83a1102ccbb5c9dc98330aa95577
Signed-off-by: Maros Marsalek <mmarsale@cisco.com>
BUG-692 Replace strings with ModifyAction enum

Change-Id: Ie2564240eed76711437afd0428d02af26cb81cff
Signed-off-by: Maros Marsalek <mmarsale@cisco.com>
Merge "Bug-1376 Add caching for premature notifications in netconf connector"
Merge "BUG-692 Replace strings with ModifyAction enum"
Merge "Improve RpcProviderRegistry loading"