add gitconfig, update install script

gitconfig

@@ -0,0 +1,20 @@
+[core]
+excludesfile = ~/.gitignore
+
+[pull]
+ff = only
+rebase = true
+
+[merge]
+ff = only
+tool = vimdiff2
+
+[diff]
+tool = vimdiff2
+
+[rebase]
+autostash = true
+autosquash = true
+
+[log]
+abbrevcommit = true

install.sh

@@ -21,15 +21,7 @@ PACKAGES="vim zsh antibody git grc ccze bmon mtr tmux byobu htop baantibody path
 
 function setup_git {
     # set up some git stuff
-    git config --global pull.ff only
-    git config --global merge.ff only
-    git config --global merge.tool vimdiff
-
-    git config --global rebase.autosquash true
-    git config --global rebase.autostash true
-
-    git config --global log.abbrevcommit yes
-
+    git config --global include.path $DOTFILES/gitconfig
 }
 
 function install_vimrc {