FetchSourcesFromManifests creates invalid paths when github repos defined with colons and ats

As reported by Denis:

jbds sources download fails 8 out of 10 builds

[INFO] [ERROR] Failed to execute goal org.jboss.tools.tycho-plugins:repository-utils:0.23.1:fetch-sources-from-manifests (fetch-sources) on project com.jboss.devstudio.core.site: Error cloning from /home/eskimo/Projects/jbdevstudio/4.4.x/releng/jbdevstudio-product to /tmp/git@github.com:dgolovin/jbdevstudio-product-2537718c95d2ab24548eadb00174cf639ec1dd99.zip: /tmp/git@github.com:dgolovin/jbdevstudio-product-2537718c95d2ab24548eadb00174cf639ec1dd99.zip (No such file or directory)

Affected source:

https://github.com/jbosstools/jbosstools-maven-plugins/blob/master/tycho-plugins/repository-utils/src/main/java/org/jboss/tools/tycho/sitegenerator/FetchSourcesFromManifests.java

Solution:

ensure paths don't include colons, ats, or other special chars. (Replace with underscores?)