promp to 0.1
update usage
Support import options
Merge pull request #4 from shamenchens/ImportOptions

Support import options, r=gasolin
update readme and pump version to 0.2
add license
opt-in css variable replacing
append vars options in readme
Update media query readme
Support media query filter options
Merge pull request #5 from shamenchens/MediaQueryOptions

Support media query filter options, r=gasolin
Merge pull request #6 from shamenchens/UpdateReadme

Update media query readme
Update README.md
Update README.md
Update package.json
Update README.md
 rename  and  option to ,  #7
add npm install instruction