Version 02
This is for programming assignment 02.
Implementation is done.
Simple test is done and of course it may be modified later for deeply test.

modified:   cachematrix.R
new file:   Rprogramming/.Rproj.user/991B146A/persistent-state
new file:   Rprogramming/.Rproj.user/991B146A/sdb/prop/4D71E956
new file:   Rprogramming/.Rproj.user/991B146A/sdb/prop/8E313AA4
new file:   Rprogramming/.Rproj.user/991B146A/sdb/prop/9DEC99B3
new file:   Rprogramming/.Rproj.user/991B146A/sdb/prop/A26B259A
new file:   Rprogramming/.Rproj.user/991B146A/sdb/prop/INDEX
new file:   Rprogramming/.Rproj.user/991B146A/sdb/s-5BA5F03F/354CD85B
new file:   Rprogramming/.Rproj.user/991B146A/sdb/s-5BA5F03F/68278A75
new file:   Rprogramming/.Rproj.user/991B146A/sdb/s-5BA5F03F/778D01CC
new file:   Rprogramming/.Rproj.user/991B146A/sdb/s-5BA5F03F/83B6CC80
new file:   Rprogramming/.Rproj.user/991B146A/sdb/s-5BA5F03F/D907546B
new file:   Rprogramming/.Rproj.user/991B146A/sdb/s-5BA5F03F/FC8BE1DE
new file:   Rprogramming/.Rproj.user/991B146A/sdb/s-5BA5F03F/lock_file
new file:   Rprogramming/ProgrammingAssignment2/README.md
new file:   Rprogramming/ProgrammingAssignment2/cachematrix.R
Merge branch 'master' of https://github.com/zhushun0008/datasciencecoursera