server: add debug log module to server

packages/server/lib/log.coffee

@@ -0,0 +1,9 @@
+# lightweight logging for Node
+# only shows log messages if running with
+#   DEBUG=cypress:start ...
+# or
+#   DEBUG=cypress:* ...
+# use
+#   log = require('./log')
+#   log('working in %s', process.cwd())
+module.exports = require('debug')('cypress:server')

packages/server/lib/saved_state.coffee

@@ -1,5 +1,8 @@
 FileUtil = require("./util/file")
 appData = require("./util/app_data")
+log = require('./log')
+
+log('making saved state from %s', process.cwd())
 
 module.exports = new FileUtil({
   path: appData.path("state.json")

packages/server/package.json

@@ -94,6 +94,7 @@
     "cookie": "^0.2.3",
     "cookie-parser": "^1.3.3",
     "data-uri-to-buffer": "0.0.4",
+    "debug": "^2.6.8",
     "electron-context-menu": "^0.8.0",
     "electron-positioner": "3.0.0",
     "errorhandler": "1.1.1",