ability to add @import statements for resources(mixins) from other extensions #56
Description
Use Case:
theme_bootstrap4 ships a fully fledged and well configurable scss/css stack for bootstrap.
In our own extension we add some additional scss/css. Now we would like to make use of the bootstrap mixins inside our scss.
@import "../../../../theme_bootstrap4/Resources/Public/Contrib/Bootstrap/scss/mixins";
This just does not work currently.
If 'EXT:theme_bootstrap4' resolving would work this would be awesome, other than that relative paths like above would be fine as well.