git: replace diff-so-fancy with delta

diff-so-fancy does not work on `git add -p`, but delta does.

There had been a long discussion on the --patch issue in
diff-so-fancy[0] and the problems there, happen during git add, too.

Some commits [1] are referencing this issue. Here it got replaced with
delta.

After some checks, it seems to work fine and much better than
diff-so-fancy.

[0] so-fancy/diff-so-fancy#35
[1] arcticicestudio/igloo@4815419

.gitmodules

@@ -6,9 +6,6 @@
 	path = zsh/oh-my-zsh
 	url = https://github.com/robbyrussell/oh-my-zsh
 	branch = master
-[submodule "git/diff-so-fancy"]
-	path = git/diff-so-fancy
-	url = https://github.com/stevemao/diff-so-fancy.git
 [submodule "zsh/zsh-syntax-highlighting"]
 	path = zsh/zsh-syntax-highlighting
 	url = https://github.com/zsh-users/zsh-syntax-highlighting

git/gitconfig

@@ -17,7 +17,7 @@
 [core]
 	editor = vim
 	eol = native
-	pager = diff-so-fancy | less --tabs=4 -RFX
+	pager = delta
 [alias]
 	ct         = log --graph --decorate --pretty=oneline --abbrev-commit
 	committree = log --graph --decorate --pretty=oneline --abbrev-commit
@@ -36,8 +36,15 @@
 	fetch = +refs/merge-requests/*/head:refs/remotes/origin/merge-requests/*
 [diff]
 	tool = vimdiff
+	colorMoved = default
 [difftool]
 	prompt = false
+[interactive]
+	diffFilter = delta --color-only
+[delta]
+	navigate = true
+	light = false
+	line-numbers = true
 [color "diff-highlight"]
 	oldNormal = red
 	oldHighlight = red bold 52