move main file
isolate lib/parser.js to an individual module: argv-parser
fixes #2: provide a tool method to handle errors when parsing options
fixes #2: support logs when parsing options
support options.context; fixes #6
update fs-sync to 0.2.1
fix argv offset
refractor the implementation of context; no longer use `call`; update README.md and sample files
improve performance; add a new parameter so we can manually call `run` method
add logger to commander
add logger to commander
set `get_commander` method as a public method
.run() method will use no default callback handler
fix a potential problem if there are more than one comfort instances
create a new commander object when we first use the command
fix built-in help command
fix dependencies
fix logger
fix logger
fix print method