Added more utilities in JsonUtils/Joltutils

      moved methods not from JsonUtil interface to JoltUtils
      added methods:
      navigateSafe
      isEmptyJson
      listKeyChains
      added tests
      Marked older methods as depricated

Change-Id: I34e6b940f1d96580d5685edca3c8603aa388fad8

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Change-Id: I164749068ab32ac5a05b4be8a1611db1d3ffaafa