I changed the name of branch to ref in the git install addon command... but there's still some problems it seems like:
[Desktop]$ addon-install-from-git --url https://github.com/bsorrentino/maven-confluence-reporting-plugin.git --coordinate org.jboss.forge.addon:confluence --ref v4
***INFO*** Installing Addon from Git [0/4] ...
***INFO*** Installing Addon from Git:Cloning repository in /var/folders/qp/tx3m3_49487d60x3b429p8g40000gn/T/1403217372628-0 [0/4] ...
***ERROR*** Ref v4 already exists
Not sure what is going on here. Could you take a look?--
Lincoln Baxter, III
"Simpler is better."