Implement TSQL specific function call mapper

[jimidle]

Here, we implement the function call mapper (Rule) that allows us to make complex transformations from TSQL specific functions into Databricks compatible constructs. Transformations are sometimes argument reordering, and sometimes replacement with a different expression.

In this PR we use the transformation of TSQL DATEADD to Databricks SQL DATE_ADD, ADD_MONTHS and xxx + INTERVAL n {days|months|etc}

For example the TSQL:

SELECT DATEADD(hh, 7, col1) AS add_hours_col1 FROM tabl;

Translates to:

SELECT col1 + INTERVAL 7 HOUR AS add_hours_col1 FROM tabl;

[github-actions[bot]]

Coverage tests results

401 tests  ±0   135 :white_check_mark: +26   4s :stopwatch: ±0s   2 suites ±0     0 :zzz: ± 0    2 files   ±0   266 :x:  - 26 

For more details on these failures, see this check.

Results for commit 1cc34125. ± Comparison against base commit 94a3690f.

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