updated: Github's new markdown feature

https://github.com/blog/1841-nested-task-lists
No more unicode checkboxes
Deleting Colons

no need for them, too.
Update free-courses-en.md
Included jquery and JS tuts from codecademy..
Sorted Index and ios section
Sorted Java & Python courses., 

Removed interactive tutorial from javascript..
Merge pull request #976 from avinoth/master

Sorted Courses section & added two courses in interactive tutorial
+ A Visual Git Reference
Extra line
Merge pull request #977 from hoganlong/alpha-en

A Visual Git Reference
Removed Explore flask link - not free
sorted things..
sorting..:bowtie:
Merge pull request #978 from avinoth/master

Removed false link and sorted things..
Close #980
Remove dead links, close #979
+ Basic JavaScript for the impatient programmer
Merge pull request #981 from hoganlong/working-branch

+ Basic JavaScript for the impatient programmer
fixes #949