(#2632) - remove browserified Buffer from build

So apparently Browserify does this thing where,
if you do "./mydep": "false", you need to reference
all possible relative paths used to that dependency,
whereas if you just swap it out for an empty
implementation then it works regardless of the relative
path used.

This solution is dumb, but it cuts down the min+gz size
from 51185 to 46298.

lib/adapters/http/http.js

diff --git a/lib/adapters/http/http.js b/lib/adapters/http/http.js
index f154438..66e21cf 100644
--- a/lib/adapters/http/http.js
+++ b/lib/adapters/http/http.js
@@ -13,6 +13,7 @@
 var errors = require('../../deps/errors');
 var log = require('debug')('pouchdb:http');
 var isBrowser = typeof process === 'undefined' || process.browser;
+var buffer = require('../../deps/buffer');
 
 function encodeDocId(id) {
   if (/^_(design|local)/.test(id)) {
@@ -470,7 +471,7 @@
       if (isBrowser) {
         blob = utils.createBlob([utils.fixBinary(binary)], {type: type});
       } else {
-        blob = binary ? new Buffer(binary, 'binary') : '';
+        blob = binary ? new buffer(binary, 'binary') : '';
       }
     }
 

lib/deps/buffer-browser.js

diff --git a/lib/deps/buffer-browser.js b/lib/deps/buffer-browser.js
new file mode 100644
index 0000000..67af5e6
--- /dev/null
+++ b/lib/deps/buffer-browser.js
@@ -0,0 +1,2 @@
+// hey guess what, we don't need this in the browser
+module.exports = {};
\ No newline at end of file

package.json

diff --git a/package.json b/package.json
index f691dc8..3215367 100644
--- a/package.json
+++ b/package.json
@@ -96,7 +96,6 @@
     "build-perf": "browserify tests/performance/*.js > tests/performance-bundle.js"
   },
   "browser": {
-    "./deps/buffer": false,
     "request": false,
     "crypto": false,
     "./adapters/leveldb/leveldb": false,
@@ -104,6 +103,7 @@
     "./lib/deps/ajax.js": "./lib/deps/ajax-browser.js",
     "./lib/version.js": "./lib/version-browser.js",
     "./lib/adapters/preferredAdapters.js": "./lib/adapters/preferredAdapters-browser.js",
+    "./lib/deps/buffer.js": "./lib/deps/buffer-browser.js",
     "bluebird": "lie",
     "leveldown": "level-js",
     "fs": false