[fix_jira_143] Updated version of some plugins.
               Changed scm from svn to git (on GitHub).
               Updated version of mind-maven-skin used in site.xml.
               Updated version of mind-parent in mind-maven-skin/pom.xml.
               Added a contributor.
[fix_jira_143] Updated version of some plugins.

cobertura-maven-plugin 2.5.1 -> 2.6
maven-assembly-plugin 2.3 -> 2.4
docbkx-maven-plugin 2.0.12 -> 2.0.15
maven-site-plugin 3.0 ->3.3
Merge pull request #1 from valeriebertin/fix_jira_143

Fix_jira_143 - Updated version of several plugins.