Packages are reorganized to improve logical order

[izgeri]

This project has evolved to a point where the packages could use an effort to reorganize them so they are more logically distinct units. For example,

• the github package includes suite-related info (eg SuiteComponent and SuiteCategory) that may be better relegated to its own package
• the repositories package really includes info pulled from the suite.yml, eg config, section, and category - it's not a pure library for aggregating info about repositories
• the template package leverages the github.SuiteCategories object that should probably come from a package other than github

In addition, the templates test "is at the far edge of explicit test data definition bulk limit" -- @sgnn7, and should maybe be refactored as part of this effort.