Evidently

**Updates:**
- Replaced BaseWidgetInfo with helpers: https://github.com/evidentlyai/evidently/pull/326
- Added metrics generator for column-based metrics: https://github.com/evidentlyai/evidently/pull/323
- Added black and isort: https://github.com/evidentlyai/evidently/pull/322

**Fixes:**
- https://github.com/evidentlyai/evidently/pull/340
- https://github.com/evidentlyai/evidently/pull/341
- https://github.com/evidentlyai/evidently/pull/336

**Updates:**
- Introduced Report - an object, that unites Dashboard and Profile functionality
- Introduced MetricPreset - an object, that replaces Tab and ProfileSection
- Implemented following MetricPresets: DataDrift, DataQuality (limited content), CatTargetDrift, NumTargetDrift, RegressionPerformance, ClassificationPerformance

**Fixes:**
- 312

**Updates:**
- Implemented function generate_column_tests() to generate similar tests for many columns automatically

Dataset Null-related tests
- Implemented TestNumberOfNulls to replace TestNumberOfNANs and TestNumberOfNullValues
- Implemented TestShareOfNulls
- Implemented TestShareOfColumnsWithNulls
- Implemented TestShareOfRowsWithNulls
- Implemented TestNumberOfDifferentNulls

Column Null-related tests
- Implemented TestColumnNumberOfNulls to replace TestColumnNumberOfNullValues
- Implemented TestColumnShareOfNulls to replace TestColumnNANShare

**Fixes:**
- Fixed metric duplication to reduce an amount of calculations while building TestSuites (basically, now same metrics from the one test suite are not recalculated multiple times)
- Implemented NAN filtering for all dashboards in way, that each column is filtered separately

Updates:
- added TPR, TNR, FPR, FNR Tests for Binary Classification Model Performance
- Renamed status "No Group" to "Dataset-level tests" in TestSuites filtering menu

Fixes:
- 207
- 265
- 256
- fixed unit tests for different versions of python and pandas

**Updates:**
1. Updated the UI to let users group tests by the following properties:
- All tests
- By Status
- By feature
- By test type
- By test group

2. New Tests:
- Added tests for binary probabilistic classification models
- Added tests for multiclass classification models
- Added tests for multiclass probabilistic classification models
The full list of tests will be available in the docs.

3. New Tests Presets:
- Regression
- MulticlassClassification
- BinaryClassificationTopK
- BinaryClassification

* added default configurations for Data Quality Tests
* added default configurations for Data Integrity Tests
* added visualisation for Data Quality Tests
* added visualisation for Data Integrity Tests
* Test descriptions are updated (column names are highlighted)