Add a function to configure dependencies and repositories in gradle-like manner

[altavir]

File-level annotations seem to be rather artificial for the notebook. I propose to add a configuration function that will contatin all necesary repositories and dependencies notations. So instead of writing

@file:Repository("https://repo.kotlin.link")
@file:DependsOn("space.kscience:plotlykt-jupyter:0.5.0")

we could do

notebook.configure{
  repositories{
    maven("https://repo.kotlin.link")
  }
  dependencies{
    implementation("space.kscience:plotlykt-jupyter:0.5.0")
  }
}

I specifically made the design exatly the same as gradle configuration. People could just copy configuration blocks from library descriptions or even from mavenCentral.

The configuration could be simplified with some shortcuts

notebook.repositories.maven("https://repo.kotlin.link")
notebook.dependencies += "space.kscience:plotlykt-jupyter:0.5.0"

Later some additional configuraion options could be added in the same configuration block.

[ileasile]

Yes, it's doable