fix(bin) wrong path to ValidationError module

[thibaultcha]

Apparently this error only happens on master (not on the latest v1.16.2).

Before:

$ bin/httpsnippet
module.js:338
throw err;
^
Error: Cannot find module 'har-validator/src/error'
at Function.Module._resolveFilename (module.js:336:15)
at Function.Module._load (module.js:278:25)
at Module.require (module.js:365:17)
at require (module.js:384:17)
at Object.<anonymous> (/Users/thibaultcha/Projects/mashape/httpsnippet/bin/httpsnippet:13:23)
at Module._compile (module.js:460:26)
at Object.Module._extensions..js (module.js:478:10)
at Module.load (module.js:355:32)
at Function.Module._load (module.js:310:12)
at Function.Module.runMain (module.js:501:10)
at startup (node.js:129:16)
at node.js:814:3

After:

$ bin/httpsnippet
Usage: httpsnippet [options] <files ...>
Options:
-h, --help output usage information
-V, --version output the version number
-t, --target <target> target output
-c, --client [client] target client library
-o, --output <directory> write output to directory

[thibaultcha]

I am getting another error now:

$ bin/httpsnippet ~/Desktop/use-case.json --target objc --client nsurlsession
✖ use-case.json fail: Catch filter must inherit from Error or be a simple predicate function
See http://goo.gl/o84o68

[thibaultcha]

I'll work against 1.16.2 for now.