Add .fxrc support (#22)

README.md

@@ -121,6 +121,28 @@ $ npm install -g lodash
 $ cat package.json | fx 'require("lodash").keys(this.dependencies)'
 ```
 
+### Using .fxrc
+
+Create _.fxrc_ file in `$HOME` directory, and require any packages or define global functions.
+
+For example, access all lodash methods without `_` prefix. Put in your `.fxrc` file:
+
+```js
+Object.assign(global, require('lodash'))
+```
+
+And now you will be able to call all lodash methods. For example, see who's been committing to react recently:
+
+```
+curl 'https://api.github.com/repos/facebook/react/commits?per_page=100' \
+| fx 'mapValues(groupBy(this, "commit.committer.name"), size)'
+```
+
+> To be able require global modules make sure you have correct `NODE_PATH` env variable.
+> ```bash
+> export NODE_PATH=/usr/local/lib/node_modules
+> ```
+
 ### Formatting
 
 If you need something different then JSON (for example arguments for xargs) do not return anything from reducer.

index.js

@@ -1,6 +1,17 @@
 #!/usr/bin/env node
 'use strict'
+const os = require('os')
+const path = require('path')
 const pretty = require('@medv/prettyjson')
+const {stdin, stdout, stderr} = process
+
+try {
+  require(path.join(os.homedir(), '.fxrc'))
+} catch (err) {
+  if (err.code !== 'MODULE_NOT_FOUND') {
+    throw err
+  }
+}
 
 const usage = `
   Usage
@@ -28,8 +39,6 @@ const usage = `
 `
 
 function main(input) {
-  const {stdout, stderr} = process
-
   if (input === '') {
     stderr.write(usage)
     process.exit(2)
@@ -88,15 +97,13 @@ function reduce(json, code) {
 }
 
 function run() {
-  const stdin = process.stdin
   stdin.setEncoding('utf8')
 
-  let buff = ''
-
   if (stdin.isTTY) {
     main('')
   }
 
+  let buff = ''
   stdin.on('readable', () => {
     let chunk