ports: download vim archive from github

The FTP download was shaky and according to
https://www.vim.org/download.php, GitHub is the recommended way to
obtain vim.

Fixes #2943

repos/ports/ports/vim.hash

@@ -1 +1 @@
-768760df2101dc5fe3b46b663bea67530427e872
+53caaaa7542e262f983eda2d44a0b4d4a7b3243d

repos/ports/ports/vim.port

@@ -2,8 +2,8 @@ LICENSE   := Vim
 VERSION   := 7.3
 DOWNLOADS := vim.archive
 
-URL(vim) := ftp://ftp.vim.org/pub/vim/unix/vim-$(VERSION).tar.bz2
-SHA(vim) := 5c5d5d6e07f1bbc49b6fe3906ff8a7e39b049928b68195b38e3e3d347100221d
+URL(vim) := https://github.com/vim/vim/archive/v$(VERSION).tar.gz
+SHA(vim) := 56f330c33411d4fd3ae2017ea26b07b8bff9b3ac712d5a77f79ccd5374ee39f4
 DIR(vim) := src/noux-pkg/vim
 
 PATCHES := src/noux-pkg/vim/build.patch