Rewrite tests on models utilizing Factory Girl

[completes #66961022]
test for current_employee in EmployeesController
Write tests for employer model using FactoryGirl, and made factory files for testing
[completes 66995176]
Add tests for .top_tags and .calculate_top_tags_score
[completes #67078740]
Merge test files 3/7/14
Merge branch 'master' of github.com:HowHai/j0bD