Use spm_modules as moduleDir by default

Closes #19
remove parsing on need #20
File object extends vinyl
feat(package)  api change

- change: get -> getPackage
- change: set -> setPackage
- new: getFile
- new: getFiles

Closes #23
update doc and hist
refactor(package) only dependencies use getter/setter

just copy properties instead of exportsPorperty, and parse
dependencies and devDependencies in resolveDeps
refactor(package) simplify _parseFiles
refactor(file) file will not be parsed  when ignore
fix(package) ignore package like `a/a.js`
doc(history) update hist
bump 0.10.0
Merge pull request #24 from popomore/0.10.x

0.10.x