Use markdown for readme (#3)

* Use markdown for readme, format it more nicely

* Update README.md

Author: danirabbit

README

@@ -0,0 +1,28 @@
+# Pantheon Camera
+
+The camera app designed for elementary OS
+
+## Building, Testing, and Installation
+
+You'll need the following dependencies:
+
+ - valac-0.30
+ - libgtk-3.0-dev
+ - libgranite-dev
+ - libclutter-gst-3.0-dev
+ - libclutter-gtk-1.0-dev
+
+It's recommended to create a clean build environment
+
+    mkdir build
+    cd build/
+    
+Run `cmake` to configure the build environment and then make to build
+
+    cmake -DCMAKE_INSTALL_PREFIX=/usr ..
+    make
+    
+To install, use `make install`, then execute with `snap-photobooth`
+
+    sudo make install
+    snap-photobooth