Add a README

README.md

+# Vim syntax files
+
+There is actually only one file here yet: for the minijazz programming language
+
+## How to
+
+The recommended way to install those files is:
+
+1. Clone the repository somewhere on your system
+2. For each `foo.vim`, create a symlink
+
+    `~/.vim/syntax/foo.vim -> $REPO_FOLDER/foo.vim`
+
+   Create the folder `~/.vim/syntax` if necessary.
+
+3. Activate the syntax option and bind minijazz to the `.mj` extension by adding
+   the following two lines in your `.vimrc` (or `~/.vim/vimrc`)
+
+    syntax on
+    autocmd BufRead,BufNewFile,BufFilePre *.mj setfiletype mj