Adding Impala page, add link to index.
Merge pull request #16 from kite-sdk/addImpala

Adding Impala page, add link to index.
Updates and corrections to V-W-Impala.
Merge pull request #17 from kite-sdk/updateImpala

Updates and corrections to V-W-Impala.
One wafer-thin fix to a heading
Merge pull request #18 from kite-sdk/oopsImpala

One wafer-thin fix to a heading
Remove link to CSV files, which never existed, honest.
Merge pull request #19 from kite-sdk/reviseImpalaExample

Remove link to CSV files, which never existed, honest.
Revised for new sample data
Merge pull request #20 from kite-sdk/updateImpala

Revised for new sample data
Updated examples with more realistic ratings.
Merge pull request #21 from kite-sdk/anotherImpalaChange

Updated examples with more realistic ratings.
Updated URL to staged CLI Jar in 2 docs.
Update Viewing-with-Impala.md

Added "from" to schema heading
Add article on schema evolution.