don't set foldmethod=syntax by default

Overwriting the user's modeline is probably a bad idea. Instead make a
hint in the documentation and let the users set it themselves.

Fixes #31

Signed-off-by: Roland Hieber <[email protected]>

Author: rohieb

doc/ledger.txt

@@ -30,6 +30,10 @@ TIPS                                                             *ledger-tips*
 
 Tips and useful commands
 
+* vim-ledger can do syntax-sensitive folding when you set `foldmethod=syntax`
+  in the |modeline| of your ledger file. This way transactions can shrink down
+  to just one line.
+
 * Try account-completion (as explained below). If you use YouCompleteMe, you
   should disable it for Ledger files. Put this in your .vimrc:
 

ftplugin/ledger.vim

@@ -10,11 +10,10 @@ endif
 let b:did_ftplugin = 1
 
 let b:undo_ftplugin = "setlocal ".
-                    \ "foldmethod< foldtext< ".
+                    \ "foldtext< ".
                     \ "include< comments< commentstring< omnifunc< formatprg<"
 
 setl foldtext=LedgerFoldText()
-setl foldmethod=syntax
 setl include=^!\\?include
 setl comments=b:;
 setl commentstring=;%s