Enable 3.8.x builds on Travis

[nvoxland]

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Liquibase Version: '3.8.x'

• [X ] Bug fix (non-breaking change which fixes an issue)
• Enhancement/New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Description

Applying Travis config from master to the 3.8.x branch

Fast Track PR Acceptance Checklist:

• Build is successful and all new and existing tests pass
• Added Unit Test(s)
• Added Integration Test(s)
• Documentation Updated

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (3.8.x@7124bba). Click here to learn what that means.
The diff coverage is n/a.

@@           Coverage Diff            @@
##             3.8.x    #1075   +/-   ##
========================================
  Coverage         ?   47.95%           
  Complexity       ?     7310           
========================================
  Files            ?      725           
  Lines            ?    35218           
  Branches         ?     6488           
========================================
  Hits             ?    16888           
  Misses           ?    16009           
  Partials         ?     2321           

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