no aggregate/query/session stats published when interval.time or limit.time set to negative values

[Feng, Qiang]

Negative values should work as default 60. But with negative values, the process will halt and no statistics published.

Scenarios:

interval.time = 1, limit.time = -1
    a. no aggr stats.
    b. no query stats. Query ran for 01:35 did not publish.
    c. no session stats.

 interval.time = -1, limit.time = 1
    a. no aggr stats.
    b. no query stats. Query ran for 01:35 did not publish.
    c. no session stats.

[Judy Zhao (hongxia-zhao)]

Please check here for the fixing <https://review.trafodion.org/#/c/1707/>