Enhanced vim support.

This brings the utils/vim folder into a more vim-like format by moving
the syntax hightlighting files into a syntax subdirectory. It adds
some minimal settings that everyone should agree on to ftdetect/ftplugin and
features a new indentation plugin for .ll files.

llvm-svn: 235369
diff --git a/llvm/utils/vim/ftplugin/tablegen.vim b/llvm/utils/vim/ftplugin/tablegen.vim
new file mode 100644
index 0000000..cfae846
--- /dev/null
+++ b/llvm/utils/vim/ftplugin/tablegen.vim
@@ -0,0 +1,12 @@
+" Vim filetype plugin file
+" Language: LLVM TableGen
+" Maintainer: The LLVM team, http://llvm.org/
+
+if exists("b:did_ftplugin")
+  finish
+endif
+let b:did_ftplugin = 1
+
+setlocal matchpairs+=<:>
+setlocal softtabstop=2 shiftwidth=2
+setlocal expandtab