write IMSI to config file.
fix bug. it will destroy config.txt in some cases
add CC=arm-linux-gcc in Makefile of chat and pppd. make compile more conviniently.
add all scripte into repo. ppp_update.sh is too upate the whole ppp for pos. create_tar.sh is to create tar package for ppp update
strip to make image smaller
Merge branch 'master' of https://github.com/RandolphWang1/yr_ppp
fix a bug.