Update free-podcasts-screencasts-en.md

Added CSS-Tricks Screencast resource
Update free-podcasts-screencasts-en.md

updated chronological order (A->Z)
Update free-podcasts-screencasts-en.md

Added Angular JS podcast link
Update free-podcasts-screencasts-en.md

Corrected hash-link
Merge pull request #1278 from charles-kibue/css-cast

CSS, Angular casts