feat: Added two classification examples using Vowpal Wabbit

[chenhuims]

• One example uses Sentiment140 data for twitter sentiment classification
• The other example applies VW algorithm to the adult census dataset

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[drdarshan]

Thank you for this contribution! Could you please remove the output cells (esp. ones with images) and resubmit the PR? I'll sign off.

[drdarshan]

Thanks again for your contribution.

[mhamilton723]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[codecov]

Codecov Report

Merging #733 into master will increase coverage by 11.56%.
The diff coverage is n/a.

@@             Coverage Diff             @@
##           master     #733       +/-   ##
===========================================
+ Coverage   68.56%   80.13%   +11.56%     
===========================================
  Files         230      230               
  Lines        9197     9197               
  Branches      504      504               
===========================================
+ Hits         6306     7370     +1064     
+ Misses       2891     1827     -1064

Impacted Files	Coverage Δ
...osoft/ml/spark/io/http/PartitionConsolidator.scala	95.55% <0%> (+2.22%)	⬆️
...m/microsoft/ml/spark/io/http/HTTPTransformer.scala	97.5% <0%> (+2.5%)	⬆️
...om/microsoft/ml/spark/lightgbm/LightGBMUtils.scala	94.93% <0%> (+2.53%)	⬆️
...com/microsoft/ml/spark/core/contracts/Params.scala	95.74% <0%> (+4.25%)	⬆️
...a/com/microsoft/ml/spark/io/http/HTTPClients.scala	57.14% <0%> (+5.35%)	⬆️
...icrosoft/ml/spark/downloader/ModelDownloader.scala	85.88% <0%> (+5.88%)	⬆️
...scala/com/microsoft/ml/spark/io/http/Parsers.scala	75% <0%> (+6.25%)	⬆️
...a/com/microsoft/ml/spark/lightgbm/TrainUtils.scala	91.03% <0%> (+8.96%)	⬆️
...n/scala/org/apache/spark/ml/param/ArrayParam.scala	70% <0%> (+10%)	⬆️
...rosoft/ml/spark/core/schema/BinaryFileSchema.scala	100% <0%> (+12.5%)	⬆️
... and 24 more

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[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[mhamilton723]

@chenhuims Looks like the data download and load didnt work. your dispay df shows 0 rows. It might have something to do with the schema you provided. Try with inferSchema set to true instead of making and passing a schema.

[chenhuims]

@chenhuims Looks like the data download and load didnt work. your dispay df shows 0 rows. It might have something to do with the schema you provided. Try with inferSchema set to true instead of making and passing a schema.

Thanks for checking. There was indeed some issue with data downloading. I will try to fix this issue.

[chenhuims]

@mhamilton723 I made a fix and the notebook runs without issue on my ADB workspace. However, the E2E test still failed. Could you grant me access to the ADB workspace of the testing pipeline so I can check the detailed logs?

[chenhuims]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

[chenhuims]

/azp run

[azure-pipelines]

Azure Pipelines successfully started running 1 pipeline(s).

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