Add --no-peer option

Fixes #81

Author: voxpelli

cli.js

@@ -29,6 +29,7 @@ if (args.help || args._.length === 0) {
   console.log('--missing (default)   Check to make sure that all modules in your code are listed in your package.json')
   console.log('--unused, --extra     The inverse of the --missing check and will tell you which modules in your package.json *were not* used in your code')
   console.log("--no-dev              Won't tell you about devDependencies that are missing or unused")
+  console.log("--no-peer             Won't tell you about peerDependencies that are missing or unused")
   console.log("--ignore-module, -i   Won't tell you about these module names when missing or unused")
   console.log('--entry               By default your main and bin entries from package.json will be parsed, but you can add more the list of entries by passing them in as --entry')
   console.log("--no-default-entries  Won't parse your main and bin entries from package.json will be parsed")
@@ -78,6 +79,7 @@ check({
   var failed = 0
   var options = {
     excludeDev: args.dev === false,
+    excludePeer: args.peer === false,
     ignore: [].concat(args.i || [])
   }
   if (args.extra) {

index.js

@@ -109,6 +109,10 @@ function configure (pkg, options) {
 
   if (typeof ignore === 'string') ignore = [ignore]
 
+  if (!options.excludePeer) {
+    allDeps = allDeps.concat(Object.keys(pkg.peerDependencies || {}))
+  }
+
   if (!options.excludeDev) {
     allDeps = allDeps.concat(Object.keys(pkg.devDependencies || {}))
   }