Create a base class for project settings

[Dovyski]

A project settings panel should extend a base class (e.g. Codebot.Panel.ProjectSettings). It will make the job of integrating global Codebot features (e.g. edit project name) into different project types (js, flash, etc) a lot easier.

Right now, each platform type has its own project settings panel, which leads to code replication if they all implement the very same thing (e.g. edit project name). A base class would eliminate that in a nice way, paving the way for global features for all project type.