Allow adding custom remote repositories to MavenPomResolver

[martinbomio]

Hello! I've been trying to use sbt-pom-resolver with a structure where the parent pom repo imports another pom which comes from a custom remote repository, but been getting the following error:

[FATAL] Non-resolvable parent POM for com.foo.ml:monofonix-parent:0.1.0-SNAPSHOT: Could not transfer artifact com.foo:root:pom:148 from/to central (http://repo.maven.apache.org/maven2): HTTPS Required (501) and 'parent.relativePath' points at wrong local POM @ com.foo.ml:monofonix-parent:0.1.0-SNAPSHOT, /Users/martinbomio/Foo/Projects/monofonix/pom.xml, line 5, column 11

Seems like the default remote repository is set here https://github.com/sbt/sbt-pom-reader/blob/master/src/main/scala/com/typesafe/sbt/pom/MavenPomResolver.scala#L29.

Would it be possible to configure the remote repositories to look for the pom to resolve the effective pom?