Gets the learner short.names of the learners used in a benchmark experiment.
getBMRLearnerShortNames(bmr)(BenchmarkResult) Benchmark result.
(character).
Other benchmark: BenchmarkResult,
  batchmark, benchmark,
  convertBMRToRankMatrix,
  friedmanPostHocTestBMR,
  friedmanTestBMR,
  generateCritDifferencesData,
  getBMRAggrPerformances,
  getBMRFeatSelResults,
  getBMRFilteredFeatures,
  getBMRLearnerIds,
  getBMRLearners,
  getBMRMeasureIds,
  getBMRMeasures, getBMRModels,
  getBMRPerformances,
  getBMRPredictions,
  getBMRTaskDescs,
  getBMRTaskIds,
  getBMRTuneResults,
  plotBMRBoxplots,
  plotBMRRanksAsBarChart,
  plotBMRSummary,
  plotCritDifferences,
  reduceBatchmarkResults