Add learn lisp hard way
Add Android Succinctly book.
Added Let's learn Go! - http://go-book.appspot.com

Added Let's learn Go! - http://go-book.appspot.com
Merge pull request #1058 from levibostian/android-succinctly

Add Android Succinctly book.
Merge pull request #1059 from sugatang-itlog/master

Added Let's learn Go! - http://go-book.appspot.com
Add PowerShell Succinctly book.
Add link to PDF and Kindle for Android Succinctly

Added direct link to PDF and Kindle formats at syncfusion.com;
No login required.
Merge pull request #1062 from luis-puhl/master

Add link to PDF and Kindle for Android Succinctly
Merge pull request #1060 from levibostian/powershell-succinctly

Add PowerShell Succinctly book.
Merge pull request #1056 from vishalsodani/master

Add learn lisp the hard way book
27,000
add "The Python GTK+ 3 Tutorial"
Merge pull request #1064 from taurenchieftain/master

add "The Python GTK+ 3 Tutorial"
Fix formatting
Merge pull request #1066 from uschek/master

Fix formatting
Update CONTRIBUTING.md
Isabelle/HOL - fix anchor link

Anchor link for Isabelle/HOL was not working when viewing the Github parsed file.
Update free-programming-books.md

No longer published
Merge pull request #1070 from olso/patch-1

Update free-programming-books.md
Merge pull request #1067 from codrineugeniu/master

Isabelle/HOL - fix anchor link