add Env.java to get env properties.
add pointer.c and ignore *.out.
add return value for the main function
rename pointer.c -> pointer/mem_addr.c.
add swap.c
print the arguments of main function out.
format the c project.
start to track .project files.
fix all the warnings in c project.
add access control demo.

rule: never use public static final int[]
Merge remote-tracking branch 'github/master'