job: #1
add Tips and Tricks page contents splitted
job: #1
add Tips and Tricks page contents grouped
job: #1
- Move the content under "System Modeling . . . " folder
- Fix some grammar and format 
- Update Page Content with template changes
- Add YouTube video links
job: #1 
Move the file under "System Modeling . . . " folder
job: #1
Move files under "System Modeling . . . " folder
Merge branch 'master' of https://github.com/xtuml/training.git