Zhiping Tan 204021272
Venudhar Ravishankar 304155317


Lab 1a:
	Works in all our cases and provided cases except for subshell (if an operator is operating on two subshells, then the first
	one may not display as a subshell)
	Note: spec was not clear regarding semicolon vs. newline; every newline (except whitespace newline) is treated as exact same as semicolon,
	so semicolon (out of subshell) separates two command trees and semicolon within subshell is of type sequence command
	Does not allow input/output redirection of a subshell, but this does not matter because the specification stated that this is not required
	May have small, unlikely operator-subshell syntax error checking problems
Lab 1b:
	Executes all commands in the spec except for exec and in the order that they are given in the script
Lab 1c:
	Time travels the shell. Does not travel within subshell (i.e. sequence commands are performed in order)
Completed Feb. 13, 2014