Create plot1.R
plot1.png
added code that has been tested
Update plot1.R
added library(data.table)

to ensure that the code is self-contained.
Merge branch 'master' of https://github.com/mi6002/ExData_Plotting1

Conflicts:
	plot1.R
Delete plot1.R
uploading again
Trying again
Added Usage: data.table package must be installed
plot2 done and tested