datatarget variation included in base install

docs/Software_installation.md

@@ -32,13 +32,6 @@ DATE=`date +%Y%m%d%H%M`
 /home/u035/project/software/bcbio/tools/bin/bcbio_nextgen.py upgrade -u development --tools &> bcbio_install_upgrade_tools_${DATE}.log
 ```
 
-Install datatarget variation
-
-```
-DATE=`date +%Y%m%d%H%M`
-/home/u035/project/software/bcbio/tools/bin/bcbio_nextgen.py upgrade -u skip --datatarget variation &> bcbio_install_datatarget_variation_${DATE}.log
-```
-
 Install datatarget vep
 
 ```