fix: missing time type

[maltoze]

Currently, Executing this sql will throw exception.

SELECT CURTIME() AS result

File "<string>", line 1, in <module>
  File "/home/maltoze/repos/superset/venv/lib/python3.7/site-packages/es/baseapi.py", line 37, in wrap
    return f(self, *args, **kwargs)
  File "/home/maltoze/repos/superset/venv/lib/python3.7/site-packages/es/elastic/api.py", line 145, in execute
    self.description = get_description_from_columns(columns)
  File "/home/maltoze/repos/superset/venv/lib/python3.7/site-packages/es/baseapi.py", line 105, in get_description_from_columns
    for column in columns
  File "/home/maltoze/repos/superset/venv/lib/python3.7/site-packages/es/baseapi.py", line 105, in <listcomp>
    for column in columns
  File "/home/maltoze/repos/superset/venv/lib/python3.7/site-packages/es/baseapi.py", line 87, in get_type
    return type_map[data_type.lower()]
KeyError: 'time'

This will fix it.

[codecov-commenter]

Codecov Report

Merging #60 (ed94d95) into master (34d5b2c) will not change coverage.
The diff coverage is n/a.

❗ Current head ed94d95 differs from pull request most recent head 67a8023. Consider uploading reports for the commit 67a8023 to get more accurate results

@@           Coverage Diff           @@
##           master      #60   +/-   ##
=======================================
  Coverage   94.52%   94.52%           
=======================================
  Files          15       15           
  Lines         932      932           
=======================================
  Hits          881      881           
  Misses         51       51           

Flag	Coverage Δ
python	94.52% <ø> (ø)

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Impacted Files	Coverage Δ
es/baseapi.py	90.25% <ø> (ø)

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[dpgaspar]

LGTM, thank you!