where is git_index_add_all()?

[Freed-Wu]

Search and find no results. git_diff_*() and git_revparse_*(), too.

Maybe:

	method "add_all" {
		c_method_call "GitError"  "git_index_add_all" { "const StrArray *", "pathspec", "unsigned int", "flags", "git_index_matched_path_cb", "callback", "void *", "payload"}
	},

?

BTW, can we have a wiki like https://github.com/libgit2/libgit2sharp/wiki/ to tell user how to use lua-git2? the document is too poor.