Improve submodule reloading

This commit provides a change to clear the sys.modules cache before
importing any local package/module. This causes python to reload all
modules as soon as the FileManager.py is reloaded/imported by ST.

It is to ensure fluent plugin updates even if global variables or
module names change.

Nothing else is needed to instantly update all submodules during
development but saving the FileManager.py

This strategy is used by `A File Icon` and `GitGutter` for instance.

Author: DeathAxe

FileManager.py

@@ -1,11 +1,20 @@
 # -*- encoding: utf-8 -*-
 import os
-import imp
 import sys
 
 import sublime
 import sublime_plugin
 
+# Clear module cache to force reloading all modules of this package.
+prefix = __package__ + "."  # don't clear the base package
+for module_name in [
+    module_name
+    for module_name in sys.modules
+    if module_name.startswith(prefix) and module_name != __name__
+]:
+    del sys.modules[module_name]
+prefix = None
+
 from .libs.sublimefunctions import *
 from .commands.copy import FmCopyCommand
 from .commands.create import FmCreaterCommand, FmCreateCommand
@@ -21,20 +30,6 @@
 from .commands.open_terminal import FmOpenTerminalCommand
 from .commands.rename import FmRenameCommand, FmRenamePathCommand
 
-BASE_NAME = os.path.dirname(__file__)
-
-
-def _reload(file):
-    if file.endswith(".pyc"):
-        file = file[:-1]
-    file = file[:-3]
-    module = sys.modules.get(file.replace(os.path.sep, "."))
-    if module:
-        imp.reload(module)
-
-
-# auto reload sub files - for dev
-
 
 def plugin_loaded():
     settings = get_settings()
@@ -58,21 +53,6 @@ def plugin_loaded():
         )
 
 
-class FmDevListener(sublime_plugin.EventListener):
-    def on_post_save(self, view):
-        """Reload FileManager
-        To use this, you need to have this plugin:
-        https://github.com/math2001/sublime-plugin-reloader"""
-        if not (
-            os.path.dirname(__file__) in view.file_name()
-            and view.file_name().endswith(".py")
-        ):
-            return
-        sublime.run_command(
-            "reload_plugin", {"main": __file__, "folders": ["commands", "libs"],},
-        )
-
-
 class FmEditReplace(sublime_plugin.TextCommand):
     def run(self, edit, **kwargs):
         kwargs.get("view", self.view).replace(