* add CONTRIBUTING-de.md with German contributing guidelines.
* edit typos in CONTRIBUTING.md.
* add link to German contributing guide to language list in other contribution files, re-order list alphabetically.
* switch back the order of English and French language links in all Contribution Guidelines.
* eliminate extra spaces and put spaces in the correct positions.
* Create CONTRIBUTING-es.md
Translate to spanish
https://github.com/EbookFoundation/free-programming-books/blob/master/CONTRIBUTING.md
* Add english title anchors and other formattings
- Indent code blocks placed inside lists
- Add original (English) bookmarks above each title to allow change between language easily
- Minor text translation improvements
* Link to CONTRIBUTING-es.md
* Link to CONTRIBUTING-es.md
* Link to CONTRIBUTING-es.md
* Link to CONTRIBUTING-es.md
* Link to CONTRIBUTING-es.md
* Create CONTRIBUTING-fa_IR.md
* Fix Incorrect number of blank lines
* fix "Marker style should be `*`"
for passing Travis-CI build
* add CONTRIBUTING-fa_IR link
* add CONTRIBUTING-fa_IR link
* add CONTRIBUTING-fa_IR link
* remove 2 ebook of [Linkers and Loaders], [Learn Python The Hard Way]. ref issue:#3091, #3062
* Add CONTRIBUTING file of chinese version.
* Format text, update some description
* translate contribution md file.
* Add open Issue ref link
* Update some description in CONTRIBUTING And CONTRIBUTING-zh file.
* Update some description of zh version CONTRIBUTING.
* format md code to pass Travis CI check
* Fix The Travis CI check issue
* Fix The Travis CI check issue
* Fix The Travis CI check issue
* format md file to pass TCI check.