Is it possible to have git commit also add new files and directories?
It seems a lot of needless typing in the long run to have to type git add .
As long as I am informed right there is no such command (It could be dangerous when you have debug-files containing passwords), but if you want to simulate you could add this alias to your git config:
git config --global alias.commitx "!git add . && git commit"
Using git commitx will now run git add . followed by git commit, so you can do
git commitx -m "testing commitx on new unstaged files"