Buffer update

Documenting:

• Split README.md, cutting DATA.md and APPLYING.md out of it;
• Published a plan for the next updates in README.md;
• Updated documentation;
• Wrote the actual README.md, DATA.md and APPLYING.md (which corresponds to the current version).

Enhancements:

• Added a package qt_colored_logger.text;
• Added TextBuffer (used for console) to qt_colored_logger.text package;
• Added BasicTextBuffer (used with HTML) to qt_colored_logger.text package;
• Loggers moved from qt_colored_logger root package to nested qt_colored_logger.logger;
• Entry methods rewritten - now they do not return strings of entries, but add them to the text buffer;
• Returned protected modules, making them fully available;
• Added blanks for the next updates;
• Reworked the principle of forming strings of records in the BasicLogger, getting rid of the string variable;
• Added get_buffer() method in loggers.