added a readme and described example use case

LICENSE

@@ -1,4 +1,4 @@
-This utility is built on a modified version of tile-reduce by Mapbox, original license and 
+This utility is built on a modified version of tile-reduce by Mapbox, original license and
 copyright below:
 
 ISC License

README.md

@@ -0,0 +1,48 @@
+# Stream-Reduce
+
+This is a simplified framework built off Mapbox's [tile-reduce](//github.com/mapbox/tile-reduce) to perform map-reduce functions against large files of line-delimited JSON. This simply removes all of the `tile` processing and instead passes each new line in the file to the map script.
+
+This is currently used for geometry-reconstruction of historical OSM objects as output from the [OSM-Wayback](//github.com/osmlab/osm-wayback) utility
+
+### Example Implementation
+
+#### File: `example/index.js`
+
+    var count = 0;
+
+    streamReduce({
+      map: path.join(__dirname, 'map.js'),             //Map function
+      file: path.join(__dirname, 'file.jsonseq'),      //Input file (lines of JSON)
+      maxWorkers:10 // The number of cpus you'd like to use
+    })
+    .on('reduce', function(res) {
+      count+=res
+    })
+    .on('end', function() {
+      console.log("Finished with count value: "+count)
+    });
+
+#### File: `example/map.js`
+
+    module.exports = function(line, writeData, done) {
+      var object = JSON.parse(line.toString());
+      done(object.count)
+    })
+
+#### file.jsonseq
+
+	{"count":10}
+	{"count":10}
+	{"count":10}
+	{"count":10}
+	{"count":10}
+
+#### Use
+	$ node examples/index.js
+
+	>>Starting up 2 workers... Job started.
+	>>Processing lines from file: examples/file.jsonseq
+	>>5 lines processed in 0s.
+	>>Finished, value of count: 50
+
+

examples/file.jsonseq

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+{"count":10}
+{"count":10}
+{"count":10}
+{"count":10}
+{"count":10}

examples/index.js

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+var streamReduce = require('../src');
+var path = require('path')
+
+var count = 0;
+
+streamReduce({
+  map: path.join(__dirname, 'map.js'),
+  file: path.join(__dirname, 'file.jsonseq'),
+  maxWorkers:5 // The number of cpus you'd like to use
+})
+.on('reduce', function(res) {
+  count+=res
+})
+.on('end', function() {
+  console.log("Finished, value of count: "+count)
+});

examples/map.js

@@ -0,0 +1,8 @@
+'use strict';
+
+module.exports = function(line, writeData, done) {
+
+  var object = JSON.parse(line.toString());
+
+  done(null, object.count)
+}