cannot work with Gruntfile unless it is next to node_modules

I have a Gruntfile in a subdirectory.

I use `require('load-grunt-tasks')(grunt);` and I keep getting `Local Npm module "grunt-contrib-jshint" not found. Is it installed?` messages.

Looking at the code - the problem seems to be in loadNpmTask:

`var root = path.resolve('node_modules');`

perhaps changing it to the below will solve the problem

`var root = grunt.file.findup('node_modules');`

As a workaround I am using `--base` as suggested http://stackoverflow.com/a/20336077/1068746 but this looks more like a bug to me.

Start by locating the loadNpmTask code and reproduce the issue with a Gruntfile in a subdirectory while node_modules is elsewhere in the project. Compare the current node_modules lookup with the reported grunt.file.findup suggestion; done means local tasks such as grunt-contrib-jshint are found without requiring --base.

Written by the indexing model from the issue text.