Edits on the Introduction including more emphasis on benefits to data collector
Starting bibtex references file
Edits to Null Values section
Adding references from the Quality Control section
Merge pull request #23 from ethanwhite/section6edits

Edits to Null Values section
Merge pull request #17 from ethanwhite/introedits

Edits to the Introduction
Adding reference from section 9
Merge pull request #19 from ethanwhite/references

Starting bibtex references file