update git doc to reflect current info, switch backticks to $().

completions/git.ksh

@@ -1,4 +1,4 @@
 #: | git | add, fetch... |
 set -A complete_git_1 -- \
-	`man -cT man git | grep -o 'git-[a-z-]*' | sort -u | cut -d '-' -f2-` \
-	`git config --get-regexp ^alias\. | awk -F '[\. ]' '{ print $2 }'`
+	$(man -cT man git | grep -o 'git-[a-z-]*' | sort -u | cut -d '-' -f2-) \
+	$(git config --get-regexp ^alias\. | awk -F '[\. ]' '{ print $2 }')

completions/git.org

@@ -3,20 +3,9 @@
 The ~git~ completion currently supports the following arguments:
 
 ** Level 1
+
 #+begin_src ksh
-	add am archive \
-	bisect branch bundle \
-	checkout cherry-pick citool clean clone commit config \
-	describe diff \
-	fetch format-patch \
-	gc grep gui \
-	init \
-	log \
-	merge mv \
-	notes \
-	pull push \
-	range-diff rebase reset restore revert rm \
-	shortlog show sparse-checkout stash status submodule switch \
-	tag \
+	$(man -cT man git | grep -o 'git-[a-z-]*' | sort -u | cut -d '-' -f2-) \
+	$(git config --get-regexp ^alias\. | awk -F '[\. ]' '{ print $2 }')
 	worktree
 #+end_src

completions/man.ksh

@@ -1,7 +1,7 @@
 #: | man | man pages |
 MAN_CACHE=$LOAD_PATH/cache/man
 if [ ! -f $MAN_CACHE ]; then
-	mkdir -p `dirname ${MAN_CACHE}`
+	mkdir -p $(dirname ${MAN_CACHE})
 	ls /usr/{share,X11R6,local}/man/man[1-9] | sort -u > $MAN_CACHE
 fi