Add livy (SQL) database

[danfrankj]

WIP Adding support for livy client via pylivy

Example session

In [42]: %%livy
    ...: CREATE TABLE dan_frank.testing_metadata (foo INT, bar STRING, baz INT) USING CSV PARTITIONED BY (baz)
livy: Query: Complete after 26.23 sec on 2020-12-02.

In [45]: %%livy
    ...: INSERT INTO dan_frank.testing_metadata VALUES (123, 'abc', 42)
    ...:
livy: Query: Complete after 29.34 sec on 2020-12-02.

In [46]: %%livy
    ...: SELECT * FROM dan_frank.testing_metadata
    ...:
livy: Query: Complete after 29.22 sec on 2020-12-02.
Out[46]:
   foo  bar  baz
0  123  abc   42

TODO

• add pylivy requirement
• pass in session properties in init
• ...