add more actions; complete ctx init
fix relative paths
merge branch/cortex-2.0 to master; fix conflicts; remove unnecessary file from old 1.x branches;
update build action
remove sample command; add new action ctx server
complete cortex server
globally replace `nopt` with `option`; complete argument overloading of cortex install
UNTESTED! blind coded `ctx install`
fix a bug about option parsing
options.js: remove console.log
UNTESTED! complete programmatical api for cortex install
improve stability of arguments overloading, command/install will have no fault tolerance
remove unnecessary actions
add util lang
update README
add `validate` command
almostly complete `install` command; todo: package builder
remove bin; only support programmatical apis
add `cortex.commands.build` and related utilities
add deps: uglify-js