wrap Beremiz startup code into separate launcher class

this should make it easier to make customized version of Beremiz IDE.
It's easy to add own splash, change version, add/disable extensions
and many other things.

For example:

[----- MyBeremiz.py ------]
#!/usr/bin/env python
from BeremizIDELauncher import BeremizIDELauncher

class MyBeremizIDELauncher(BeremizIDELauncher):
def __init__(self):
BeremizIDELauncher.__init__(self)
self.splashPath = self.Bpath("", "splash.png")

def ShowSplashScreen(self):
# comment next line to disable splash entirely
BeremizIDELauncher.ShowSplashScreen(self)

# change version
import version
version.app_version = "3.141-rc52"

def LoadExtensions(self):
# add/modifine list of extensions
# in self.extensions
BeremizIDELauncher.LoadExtensions(self)

if __name__ == '__main__':
beremiz = MyBeremizIDELauncher()
beremiz.Start()

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