* Modification and New Addition of Links

Modified some links to reach the specific page and added some more links
to programming contest and problem set.

* Corrected sequence of links

* Ruby Interactive Tutorial Added

Grouped Symfony books like other frameworks and updated versions per contribution guide.

The official [Self language](http://www.selflanguage.org/) documentation.

IoT section added and IoT in five days (free software licensed) book link added for PDF EPUB (#1997)

* Added IoT section and aded IoT in five days books

* Formatting issue

* Anchor link issues

* Header spacing corrected for travis-build issue

* Adding pt_BR C book used by UFMG university

* Reordering C books list based on the CI build (142470444) error result

* Updated C language entry based on comment 231148246 from pull request 1974

Added Dayle Rees's Laravel: Code Smart book to the PHP list.

* Added IRPF90 gitbook to Misc section

* Update free-programming-books.md

* Added a bash tutorial in free-courses-en.md

* Missing PDF indication

Fix broken link.

* Add Rust podcast "New Rustacean"

* Remove trailing slash

* Adds JasperReports Section & JasperReports Ultimate Guide

* Add JasperReports section and JasperReports Ultimate Guide