merge Minh's refactor and intergration of callgraph analysis
use .? for help, so that one letter abbreviations are parse-sufficient
keep column count under 100
prompt() has to be global since a signal handler calls it
add LICENSE and LICENSE notes for libedit (under BSD)
align columns/better formating in signum.rs
track history of successfuly commands for annotation of history
implement .c for correct history only