Add possibility to apply custom options to different flows

[OlgaBielkina]

Ref issue: https://github.com/yeoman/grunt-usemin/issues/255

[sindresorhus]

// @stephanebachelier

[stephanebachelier]

@sindresorhus :+1:

Might need a little more documentation about the multiple configurations but maybe we should create a cookbook as the README is already huge.

[sindresorhus]

Might need a little more documentation about the multiple configurations but maybe we should create a cookbook as the README is already huge.

:+1:

[stephanebachelier]

@sindresorhus maybe we should accept this PR which is documented, and add a new issue for the cookbook

[sindresorhus]

Sure, but this still needs a test though.

[Frank3K]

Also needed this functionality. Patched it into my own fork, which I am using in package.json now. Excellent patch.

[stephanebachelier]

@OlgaBielkina we need a test to accept your PR. Can you provide one ?

[arthurvr]

ping @OlgaBielkina

[arthurvr]

Thannxxxx @OlgaBielkina! What do you think, @stephanebachelier?

[stephanebachelier]

@OlgaBielkina I've reviewed your tests. I didn't get where you trigger the multiple flow.

[OlgaBielkina]

@stephanebachelier as far as I understand when you use multiple flows (profiles) all previous functionality should work the same. My tests show that it works for the dev profile. All except multiple targets. With previous code base it was not possible to add dev/prod profiles at all.

[stephanebachelier]

@OlgaBielkina I will need to take some time to understand/review the whole thing. In #255 there are two kinds of demands: multiple targets and or be able to switch between dev or dist profile as you can read in #456

[stephanebachelier]

@OlgaBielkina will take a deeper look soon. Sorry for the delay there was others issues that I needed to fix before.