Refactor builders.py
Refactor builders.py

The refactoring process includes the following
1. Converted all relevant functions to use helpers.<insert function>
instead of a specific import.
2. Standardized indentation for mapping tuple
3. Add commas to last entries of mapping tuples

Change-Id: Ied80c8354b9d59639eba1a3bb9794f19d15c6ba3

wsoula/jenkins-job-builder,puppetlabs/jenkins-job-builder,gforcada/jenkins-job-builder,wsoula/jenkins-job-builder,wsoula/jenkins-job-builder,gforcada/jenkins-job-builder,gforcada/jenkins-job-builder,gforcada/jenkins-job-builder,puppetlabs/jenkins-job-builder,wsoula/jenkins-job-builder,gforcada/jenkins-job-builder,puppetlabs/jenkins-job-builder,puppetlabs/jenkins-job-builder