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ARROW-5950: [Rust][DataFusion] Add logger

It seems useful to me to do some extra (debug, info, etc) logging.

I added to the benchmark.
Executing with `RUST_LOG="debug"` gives (next to sqlparser logs):

```
[2020-12-21T23:04:59Z DEBUG datafusion::execution::context] Logical plan:
     Sort: #l_returnflag ASC NULLS FIRST, #l_linestatus ASC NULLS FIRST
      Projection: #l_returnflag, #l_linestatus, #SUM(l_quantity) AS sum_qty, #SUM(l_extendedprice) AS sum_base_price, #SUM(l_extendedprice Multiply Int64(1) Minus l_discount) AS sum_disc_price, #SUM(l_extendedprice Multiply Int64(1) Minus l_discount Multiply Int64(1) Plus l_tax) AS sum_charge, #AVG(l_quantity) AS avg_qty, #AVG(l_extendedprice) AS avg_price, #AVG(l_discount) AS avg_disc, #COUNT(UInt8(1)) AS count_order
        Aggregate: groupBy=[[#l_returnflag, #l_linestatus]], aggr=[[SUM(#l_quantity), SUM(#l_extendedprice), SUM(#l_extendedprice Multiply Int64(1) Minus #l_discount), SUM(#l_extendedprice Multiply Int64(1) Minus #l_discount Multiply Int64(1) Plus #l_tax), AVG(#l_quantity), AVG(#l_extendedprice), AVG(#l_discount), COUNT(UInt8(1))]]
          Filter: #l_shipdate LtEq CAST(Utf8("1998-09-02") AS Date32(Day))
            TableScan: lineitem projection=None
[2020-12-21T23:04:59Z DEBUG datafusion::execution::context] Optimized logical plan:
     Sort: #l_returnflag ASC NULLS FIRST, #l_linestatus ASC NULLS FIRST
      Projection: #l_returnflag, #l_linestatus, #SUM(l_quantity) AS sum_qty, #SUM(l_extendedprice) AS sum_base_price, #SUM(l_extendedprice Multiply Int64(1) Minus l_discount) AS sum_disc_price, #SUM(l_extendedprice Multiply Int64(1) Minus l_discount Multiply Int64(1) Plus l_tax) AS sum_charge, #AVG(l_quantity) AS avg_qty, #AVG(l_extendedprice) AS avg_price, #AVG(l_discount) AS avg_disc, #COUNT(UInt8(1)) AS count_order
        Aggregate: groupBy=[[#l_returnflag, #l_linestatus]], aggr=[[SUM(#l_quantity), SUM(#l_extendedprice), SUM(#l_extendedprice Multiply Int64(1) Minus #l_discount), SUM(#l_extendedprice Multiply Int64(1) Minus #l_discount Multiply Int64(1) Plus #l_tax), AVG(#l_quantity), AVG(#l_extendedprice), AVG(#l_discount), COUNT(UInt8(1))]]
          Filter: #l_shipdate LtEq CAST(Utf8("1998-09-02") AS Date32(Day))
            TableScan: lineitem projection=Some([4, 5, 6, 7, 8, 9, 10])
Query 1 iteration 9 took 802.7 ms
Query 1 avg time: 915.30 ms
```

Closes #8986 from Dandandan/add_logger

Lead-authored-by: Heres, Daniel <danielheres@gmail.com>
Co-authored-by: Daniël Heres <danielheres@gmail.com>
Signed-off-by: Andrew Lamb <andrew@nerdnetworks.org>