kitchen sink...

just gonna put the changes that I can remember making here:
 - replace blink with native completion (omnifunc)
 - remove some unneeded plugins
 - add a misc function for making sure complex bindings don't cause
   flickering
 - remove some stale snippets
 - remove folding (I don't find myself folding that often)

extras/c.sh

@@ -1,3 +0,0 @@
-# TODO:
-# add something to check if we need to run bear again to update
-# clangd build options