Bug#974030: Add the main component to Provides if it doesn't match the package name

[Julien Puydt]

Package: pkg-js-tools
Version: 0.9.45
Severity: wishlist

As discussed in #973983, it might be a good idea to make sure pkg-js-
tools adds the main component to ${nodejs:Provides} when that component
isn't the package name.

Cheers,

JP