Minor fixes to enable external submission email

• Added createchallenge stage which is NOT a stage, but a fake stage
  that runs the following stages: makedb,import,blast,challengedata. Issue #92
• Moved logic to setup logging handlers to start of celpprunner.py to remove
  no handlers found error for d3r.celpp.util. Issue #91
• Fixed bug where participant_list.csv could not be parsed if file was
  written with carriage return delimiters instead of newlines. Issue #93
• Cleaned up CELPPade by updating documentation and simplifying variable names