message: minor: Link to current ver. of C driver manual in examples/README.md
diff: ## Prerequisites
  -* `libmongoc` (see the [installation guide](http://mongoc.org/libmongoc/1.5.0/installing.html))
  +* `libmongoc` (see the [installation guide](http://mongoc.org/libmongoc/current/installing.html))
  ## Building code examples
  