title: can't find gmplot marker after doing pyinstaller
body: <p>I am using gmplot to plot markers on google map. Everything works well before doing pyinstaller to make an exe file. I am not able to do gmp.draw to draw the marker into my map.html. There are no error shown while doing pyinstaller.
  When I executing my exe file, the error shows that</p>
  <pre><code>Exception in Tkinter callback
  Traceback (most recent call last):
    File &quot;tkinter\__init__.py&quot;, line 1705, in __call__
    File &quot;test.py&quot;, line 792, in plotmap
      gmap.draw('map.html')
    File &quot;site-packages\gmplot\gmplot.py&quot;, line 1050, in draw
    File &quot;site-packages\gmplot\gmplot.py&quot;, line 1121, in _write_html
    File &quot;site-packages\gmplot\gmplot.py&quot;, line 1187, in write_points
    File &quot;site-packages\gmplot\gmplot.py&quot;, line 1228, in write_point
    File &quot;site-packages\gmplot\gmplot.py&quot;, line 164, in __init__
    File &quot;site-packages\gmplot\utility.py&quot;, line 68, in _get_embeddable_image
  FileNotFoundError: [Errno 2] No such file or directory: 'C:\\Users\\Admin\\AppData\\Local\\Temp\\_MEI366362\\gmplot\\markers/000000.png'
  </code></pre>
  <p>I tried to fix it by adding</p>
  <pre><code>gmp.coloricon = &quot;http://www.googlemapsmarkers.com/v1/%s/&quot;
  </code></pre>
  <p>but nothing change.</p>
  <p>Here are my codes about the gmplot</p>
  <pre><code>import gmplot
  import webbrowser
  from tkinter import *
  import tkinter as tk
  
  def plotmap():
      # Create the map plotter:
      apikey = '' # (your API key here)
      gmap = gmplot.GoogleMapPlotter(37.766956, -122.448481, 14, apikey=apikey)
  
      # Outline the Golden Gate Park:
      golden_gate_park = zip(*[
          (37.771269, -122.511015),
          (37.773495, -122.464830),
          (37.774797, -122.454538),
          (37.771988, -122.454018),
          (37.773646, -122.440979),
          (37.772742, -122.440797),
          (37.771096, -122.453889), 
          (37.768669, -122.453518),
          (37.766227, -122.460213),
          (37.764028, -122.510347)
      ])
      gmap.polygon(*golden_gate_park, color='cornflowerblue', edge_width=10)
  
      # Highlight some attractions:
      attractions_lats, attractions_lngs = zip(*[
          (37.769901, -122.498331),
          (37.768645, -122.475328),
          (37.771478, -122.468677),
          (37.769867, -122.466102),
          (37.767187, -122.467496),
          (37.770104, -122.470436)
      ])
      gmap.scatter(attractions_lats, attractions_lngs, color='#3B0B39', size=40, marker=False)
  
      # Mark a hidden gem:
      gmap.marker(37.770776, -122.461689, color='cornflowerblue')
  
      # Draw the map:
      gmap.draw('map.html')
      webbrowser.open('map.html')
  
  
  
  root = tk.Tk()
  b = tk.Button(root, text= &quot;plot on map&quot;, command=plotmap)
  b.pack()
  root.mainloop()
  </code></pre>