Resolve relative sass_root paths earlier

[wryk]

Revert SassCssCompiler before #64. Supports relative paths by resolving/prefixing them at extension loading. I don't know if it should be implemented this way (it feels hacky?) but I don't see how it could be better.

What do you think of this change @smnandre ?

Tests are missing because I don't know enough how asset-mapper works to design an integration test for an AssetCompiler. Testing the builder instead would be even more work for me because my dev env doesn't supports the default sass binary from the bundle.

I'll not have more time in the next weeks to work on it, feel free to modify this PR as much as you want.

[smnandre]

I'll look later this week, no immediate feedback except: i'd still start with a ".sass" check :)

[wryk]

Yeah sorry, I ignored this part on purpose and I took the conservative choice to only rollback SassCssCompiler.
I don't understand the reasoning of the current supports implementation (comparison of two realpaths) but someone might wrote it for a good reason. Because of the missing or broken tests (in my env) I'd rather not prematurely update code not required for relative path support.

[smnandre]

I mande a PR on your PR with small change suggestions :)

wryk#1

[bocharsky-bw]

Thank you!

[bocharsky-bw]

Should we merge now? Or is there still any pending work to do?

[wryk]

Based on the thread I think it's still missing tests. If I remember correctly, I didn't know (and still don't know) how to properly test these changes.
If you think the PR is sufficient, you can merge it, otherwise I will close it due to the missing tests.