Implement Logging and Devtools

[mwerezak]

Develper Tool Windows

• [x] add_debug_window
• [x] add_metrics_window
• [x] add_doc_window
• [x] add_about_window
• [x] add_style_window

Logger

• [ ] add_logger
• [ ] show_logger
• [ ] set_logger_window_title
• [ ] set_log_level
• [ ] get_log_level
• [ ] log
• [ ] log_debug
• [ ] log_error
• [ ] log_info
• [ ] log_warning
• [ ] clear_log

Other Stuff

• [ ] get_dearpygui_version

[mwerezak]

Will implement the built-in debugging window after support for 0.7 is in.