Improve the code, add some log, create influxdb sender

The plugin should now run on Sublime2 and 3
The error on send will be shown on the status bar

Added influxdb sender, the default endpoint is:
  http://localhost:8086/db/keypress/series?u=root&p=root
the default data format is:
  [{
    "name" : "devstats",
    "columns" : ["time", "filename", "key"],
    "points" : [
      [timestamp, filename, key]
    ]
  }]