code: function categorizeCommits(rawCommits) {
  
      const categorizedCommits = {};
  
      // create a bucket of rawCommits by type:
      // { fixes: [], upgrades: [], breaking: [] }
      rawCommits.forEach(function(commit) {
  
          const capType = capitalize(commit.type);
  
          if (!categorizedCommits.hasOwnProperty(capType)) {
              categorizedCommits[capType] = [];
          }
  
          categorizedCommits[capType].push(commit);
      });
  
      return categorizedCommits;
  }
docs: categorize raw commits into types of commits for consumption into md.
  @function categorizeCommits
  @param {Array} rawCommits array of objects describing commits
  @return {Object}