Software documentation and proper Readme.md (#3)

Documentation for the software and a proper Readme.md file has been added.

README.md

@@ -1,2 +1,27 @@
 # PBR-Renderer
-Sinple PBR renderer for learning purposes.
+Sinple PBR renderer for learning purposes. 
+
+![image](doc/res/tiles_render.png)
+
+## Features
+* Physically based Rendering with Cook-Torrance BRDF
+* Normal Mapping
+
+## Build instructions
+If you want to simply build and test the project type the next command and that should be it!
+``` bash
+make
+./bin/pbr
+```
+If you want to modify the code, if no more source files are created the before method would work fine. If not, project files need to be recreated, and for that the tool [premake](https://premake.github.io/) is used, specifically the fifth version. To recreate project files and rebuild 
+```bash
+premake5 gmake2
+make clean && make
+./bin/pbr
+```
+
+## Known issues
+* Nvidia users, im sorry! For reasons I don't really know, GLEW (the OpenGL loader) does not find any OpenGL version on the system. 
+
+## References
+* Great shout-out to the pages [learnopengl](https://learnopengl.com/) and [opengl-tutorial](http://www.opengl-tutorial.org/) for the great PBR theory and OpenGL tutorials.