[BASH]retrack several bash scripts
Merge branch 'master' of github.com:baodepei/working_environment
[BASH]add history settings: file size and append
[BASH]add reload .bash_history alias
[BASH]update history alias w/ append
Merge branch 'master' of github.com:baodepei/working_environment
[GDB]initial gdbinit + boost pretty printer
[EMACS]add ggtags elpa package