Update gitconfig to use osxkeychain for OSX and cache for other systems

Author: Magnus Andersson

git/gitconfig.symlink.example

@@ -7,7 +7,7 @@
         name = AUTHORNAME
         email = AUTHOREMAIL
 [credential]
-        helper = osxkeychain
+        helper = GIT_CREDENTIAL_HELPER
 [alias]
         co = checkout
         promote = !$ZSH/bin/git-promote

script/bootstrap

@@ -31,12 +31,18 @@ setup_gitconfig () {
   then
     info 'setup gitconfig'
 
+    git_credential='cache'
+    if [ "$(uname -s)" == "Darwin" ]
+    then
+      git_credential='osxkeychain'
+    fi
+
     user ' - What is your github author name?'
     read -e git_authorname
     user ' - What is your github author email?'
     read -e git_authoremail
 
-    sed -e "s/AUTHORNAME/$git_authorname/g" -e "s/AUTHOREMAIL/$git_authoremail/g" git/gitconfig.symlink.example > git/gitconfig.symlink
+    sed -e "s/AUTHORNAME/$git_authorname/g" -e "s/AUTHOREMAIL/$git_authoremail/g" -e "s/GIT_CREDENTIAL_HELPER/$git_credential/g" git/gitconfig.symlink.example > git/gitconfig.symlink
 
     success 'gitconfig'
   fi