Improve format of Glossary section in Training material guide

The format of Glossary section can be improved as follows:

• Learning Objective: A predictive statement describing the specific outcomes that a training session is intended to achieve.
• Key point: An important take home message.
• Cognitive load: This relates to the amount of information that working memory can hold at one time.
• Summative assessment: A way of evaluating the learners progress at the end of a lesson.
• Fork a repository: This makes a copy of the repository to your personal GitHub workspace.
• Make a branch: A branch is another version of the files in your repository, including a history of how files were changed from the start of the branch to the current state of files.