Fix links in doc/README.md

* Fixing the last link, which was totally broken
* Updated links in README to use relative paths.

doc/README.md

@@ -4,7 +4,7 @@
 
 Please have a look at these questions *before* opening an issue in this repo.
 
-## [Installation guide](https://github.com/PrivateBin/PrivateBin/blob/master/doc/Installation.md#installation)
+## [Installation guide](Installation.md#installation)
 
 Minimal requirements, hardening and securing your installation and initial
 configuration.
@@ -26,12 +26,12 @@ How to help translate PrivateBin and technical background on it's implementation
 
 Know how for participating in PrivateBins development.
 
-### [Generating Source Code Documentation](https://github.com/PrivateBin/PrivateBin/blob/master/doc/Generating%20Source%20Code%20Documentation.md#generating-source-code-documentation)
+### [Generating Source Code Documentation](Generating%20Source%20Code%20Documentation.md#generating-source-code-documentation)
 
 How to generate the source code API documentation, as found on the project
 website for [PHP](https://privatebin.info/codedoc/) and [JS](https://privatebin.info/jsdoc/)
 
-### [Running Unit Tests](https://github.com/PrivateBin/PrivateBin/blob/master/doc/Running Unit Tests.md#running-all-unit-tests)
+### [Running Unit Tests](Running%20Unit%20Tests.md#running-all-unit-tests)
 
 How to run the PHP & JS unit tests, including a brief introduction to property
 based unit testing.