#41: README.md, 'Execution' subsection require proper input text file
#41: README.md, minor language change
#41: README.md, 'Execution' subsection 'log/observation.log'
#41: README.md, minor language change
#41: README.md, minor language change
#41: README.md, minor language change
Merge pull request #42 from jeff1evesque/doc_execution

#41: Documentation: Further define 'Execution'