Bumping up dependencies version numbers
Using .md file extension
Updated 01-frontpage
Updated 02-preface
Updated 03-intro
Updated 04-installation
Updated 05-first-steps
Updated 06-basics
Updated 07-operators-expressions
Updated 08-control-flow
Updated 09-functions
Updated 10-modules
Updated 11-data-structures
Updated 12-problem-solving
Reformatted 13-oop
Reformatted 14-io
Reformatted 15-exceptions
Reformatted 16-standard-library
Reformatted 17-more
Reformatted 18-what-next