Rename init_shared_memory to prepare_memory #24
Description
I don't like so much the @bot.init_shared_memory/add_shared_memory_initializer names: they're too long and a bit ugly. I think a better naming is the following one:
@bot.init_shared_memory›@bot.prepare_memoryself.add_shared_memory_initializer›self.add_memory_preparer
This is a breaking change, but the old syntax will continue to work until 1.0.