[BREAKING] Update FS plugin info for python3 compat (esp8266#6807)

The FS uploader plugins need to be updated to use python3 and not
python, or they will fail on Windows (or Linux boxes without an
installed python2 interpreter).

Update the documents to point to the new versions.

doc/filesystem.rst

@@ -190,11 +190,11 @@ directory into ESP8266 flash file system.
 
 **Warning**: Due to the move from the obsolete esptool-ck.exe to the
 supported esptool.py upload tool, upgraders from pre 2.5.1 will need to
-update the ESP8266FS tool referenced below to 0.4.0 or later.  Prior versions
+update the ESP8266FS tool referenced below to 0.5.0 or later.  Prior versions
 will fail with a "esptool not found" error because they don't know how to
 use esptool.py.
 
--  Download the tool: https://github.com/esp8266/arduino-esp8266fs-plugin/releases/download/0.4.0/ESP8266FS-0.4.0.zip
+-  Download the tool: https://github.com/esp8266/arduino-esp8266fs-plugin/releases/download/0.5.0/ESP8266FS-0.5.0.zip
 -  In your Arduino sketchbook directory, create ``tools`` directory if
    it doesn't exist yet.
 -  Unpack the tool into ``tools`` directory (the path will look like
@@ -214,7 +214,7 @@ use esptool.py.
 
 *ESP8266LittleFS* is the equivalent tool for LittleFS.
 
-- Download the tool: https://github.com/earlephilhower/arduino-esp8266littlefs-plugin/releases
+- Download the 2.6.0 or later version of the tool: https://github.com/earlephilhower/arduino-esp8266littlefs-plugin/releases
 - Install as above
 - To upload a LittleFS filesystem use Tools > ESP8266 LittleFS Data Upload
 

tools/upload.py

@@ -3,8 +3,8 @@
 # Wrapper for Arduino core / others that can call esptool.py possibly multiple times
 # Adds pyserial to sys.path automatically based on the path of the current file
 
-# First parameter is pyserial path, second is esptool path, then a series of command arguments separated with --end
-# i.e. upload.py tools/pyserial tools/esptool erase_flash --end write_flash file 0x0 --end
+# First parameter is pyserial path, second is esptool path, then a series of command arguments
+# i.e. upload.py tools/pyserial tools/esptool write_flash file 0x0
 
 import sys
 import os
@@ -42,9 +42,6 @@
     elif thisarg == 'erase_region':
         erase_addr = sys.argv.pop(0)
         erase_len = sys.argv.pop(0)
-    elif thisarg == '--end':
-        # Backwards compatibility with fs upload tools, eat --end
-        pass
     elif thisarg == 'write_flash':
         write_addr = sys.argv.pop(0)
         binary = sys.argv.pop(0)