Remove last path usage from specs

This does sacrifice the ability to use Windows-style paths, but it's a
convenience function that does "magic" stuff to its argument anyways,
so I don't see it as much of a loss.

lib/specs.js

@@ -7,8 +7,7 @@
 /** IDL to protocol (services) and schema (types) parsing logic. */
 
 let files = require('./files'),
-    utils = require('./utils'),
-    path = require('path');
+    utils = require('./utils');
 
 
 // Default type references defined by Avro.
@@ -197,7 +196,7 @@ function assembleProtocol(fpath, opts, cb) {
  *
  * The parsing logic is as follows:
  *
- * + If `str` contains `path.sep` (on windows `\`, otherwise `/`) and is a path
+ * + If `str` contains `/` and is a path
  *   to an existing file, it will first be read as JSON, then as an IDL
  *   specification if JSON parsing failed. If either succeeds, the result is
  *   returned, otherwise the next steps are run using the file's content
@@ -213,7 +212,7 @@ function read(str) {
   let schema;
   if (
     typeof str == 'string' &&
-    ~str.indexOf(path.sep) &&
+    str.indexOf('/') !== -1 &&
     files.existsSync(str)
   ) {
     // Try interpreting `str` as path to a file contain a JSON schema or an IDL