[SPARK-14721][SQL] Remove HiveContext (part 2)

[andrewor14]

What changes were proposed in this pull request?

This removes the class HiveContext itself along with all code usages associated with it. The bulk of the work was already done in #12485. This is mainly just code cleanup and actually removing the class.

Note: A couple of things will break after this patch. These will be fixed separately.

• the python HiveContext
• all the documentation / comments referencing HiveContext
• there will be no more HiveContext in the REPL (fixed by [SPARK-14828][SQL] Start SparkSession in REPL instead of SQLContext #12589)

How was this patch tested?

No change in functionality.

[SparkQA]

Test build #56593 has finished for PR 12585 at commit 0e16190.

• This patch fails Spark unit tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #56592 has finished for PR 12585 at commit 8e6e2b1.

• This patch fails Spark unit tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #56617 has finished for PR 12585 at commit 069c8b6.

• This patch fails PySpark unit tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #56628 has finished for PR 12585 at commit f910821.

• This patch fails PySpark unit tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #56630 has finished for PR 12585 at commit c7bbb8f.

• This patch fails PySpark unit tests.
• This patch merges cleanly.
• This patch adds no public classes.

[andrewor14]

Hm, seems that I'll need to fix the python thing in this patch.

[SparkQA]

Test build #56722 has finished for PR 12585 at commit 188bcf0.

• This patch fails Spark unit tests.
• This patch merges cleanly.
• This patch adds no public classes.

[andrewor14]

retest this please

[SparkQA]

Test build #56756 has finished for PR 12585 at commit 188bcf0.

• This patch fails Spark unit tests.
• This patch merges cleanly.
• This patch adds no public classes.

[rxin]

The changes look good to me.

[SparkQA]

Test build #2868 has finished for PR 12585 at commit f59b869.

• This patch fails Spark unit tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #56907 has finished for PR 12585 at commit f59b869.

• This patch fails Spark unit tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #2869 has finished for PR 12585 at commit f59b869.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #2870 has finished for PR 12585 at commit f59b869.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[yhuai]

LGTM

[andrewor14]

Thanks merging into master.