Having multiple @import in one file throws a TypeError

[mcibique]

I'm using postcss-cachebuster@0.1.3 and I have css file with two imports:

@import "file1.css";
@import "file2.css";

First import is processed properly, but the second one throws an error:

TypeError: Cannot read property '1' of null
    at walkThroughtImports (C:\projects\my-project\node_modules\postcss-cachebuster\index.js:84:26)

It is caused because walkThroughtImports() uses regexp with 'g' flag but do not reset the lastIndex back to 0 after first usage. Adding pattern.lastIndex = 0; before calling pattern.exec(atrule.params) solves the problem.

[glebmachine]

Can you create a pull request, please? I will be appreciate ^__^

[mcibique]

Sure. #75