feat(install): add support for git-lfs

With git-obs-hooks replacing all .githooks, we need to add
support for git-lfs.

scripts/post-checkout.d/git-lfs.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+command -v git-lfs >/dev/null 2>&1 || { printf >&2 "\n%s\n\n" "This repository is configured for Git LFS but 'git-lfs' was not found on your path. If you no longer wish to use Git LFS, remove this hook by deleting the 'post-checkout' file in the hooks directory (set by 'core.hookspath'; usually '.git/hooks')."; exit 2; }
+git lfs post-checkout "$@"

scripts/post-commit.d/git-lfs.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+command -v git-lfs >/dev/null 2>&1 || { printf >&2 "\n%s\n\n" "This repository is configured for Git LFS but 'git-lfs' was not found on your path. If you no longer wish to use Git LFS, remove this hook by deleting the 'post-commit' file in the hooks directory (set by 'core.hookspath'; usually '.git/hooks')."; exit 2; }
+git lfs post-commit "$@"

scripts/post-merge.d/git-lfs.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+command -v git-lfs >/dev/null 2>&1 || { printf >&2 "\n%s\n\n" "This repository is configured for Git LFS but 'git-lfs' was not found on your path. If you no longer wish to use Git LFS, remove this hook by deleting the 'post-merge' file in the hooks directory (set by 'core.hookspath'; usually '.git/hooks')."; exit 2; }
+git lfs post-merge "$@"

scripts/pre-push.d/git-lfs.sh

@@ -0,0 +1,3 @@
+#!/bin/sh
+command -v git-lfs >/dev/null 2>&1 || { printf >&2 "\n%s\n\n" "This repository is configured for Git LFS but 'git-lfs' was not found on your path. If you no longer wish to use Git LFS, remove this hook by deleting the 'pre-push' file in the hooks directory (set by 'core.hookspath'; usually '.git/hooks')."; exit 2; }
+git lfs pre-push "$@"