specific requirement for thesis body
set up config, block and database of client side
add Base64, RSA, Random, etc. utils
add folder \test and implement testcase for utils
add English abstract
adjust compile.bat, close cmd window after compiling
add images for oram.png and pir.png
some adjustment on abstract
add idea.txt for ideas in ppa area
little adjustment
draft version of introduction almost complete
split approach.tex into seperated tex files
prepare to merge branches
Merge branch 'ppa-code'