Fix misleading error message from incompatible Java version

[exalate-issue-sync]

running (with Java 7):
{{bin/sparkling-shell --num-executors 3 --executor-memory 2g --master yarn --deploy-mode client}}

causes an error message:
You are trying to use Sparkling Water built for Spark 2.4.3, but your Spark is of version 52.0. Please ensure correct Spark is provided and re-run Sparkling Water.

This implies incompatible SW and Spark versions, while actual cause is incompatible Java version.

[DinukaH2O]

JIRA Issue Migration Info

Jira Issue: SW-1510
Assignee: Jakub Hava
Reporter: Tomas Pastorek
State: Resolved
Fix Version: 3.30.0.6-1
Attachments: N/A
Development PRs: Available

Linked PRs from JIRA

#2210

[hasithjp]

JIRA Issue Migration Info Cont'd

Jira Issue Created Date: 2019-08-12T04:18:57.715-0700