Can't build via gradlew

[Sairony]

Building gives the following error:

A problem occurred configuring project ':Unity Plugin'.

A problem occurred configuring project ':library'.
Could not resolve all dependencies for configuration ':library:_debugTestCompile'.
> Could not find com.android.support:support-v4:19.0.1.
Searched in the following locations:
https://raw.githubusercontent.com/onepf/OPF-mvn-repo/master/com/android/support/support-v4/19.0.1/support-v4-19.0.1.pom
https://raw.githubusercontent.com/onepf/OPF-mvn-repo/master/com/android/support/support-v4/19.0.1/support-v4-19.0.1.jar
https://jcenter.bintray.com/com/android/support/support-v4/19.0.1/support-v4-19.0.1.pom
https://jcenter.bintray.com/com/android/support/support-v4/19.0.1/support-v4-19.0.1.jar
Required by:
OpenIAB-Unity-Plugin:library:unspecified > org.robolectric:robolectric:2.3

Sure enough, neither of this locations contains support-v4-19.0.1. Since these can be found elsewhere, is there a way for me to specify a new location?