Redmine

Hi,

Redmine is a flexible project management web application. Written using the Ruby on Rails framework, it is cross-platform and cross-database.source

Redmine is an open source web application that integrates with different SCM's including Git and subversion.
Redmine supports multi-languages and can be extended with the help of plugins. It has several features. And if you wanna know about its documentation then check this outRedmine guide. Feel free to use this application for bug tracking and for project management.