Convert README to markdown

README.md

@@ -1,6 +1,4 @@
-----------------
-  RGBDS README
-----------------
+# RGBDS
 
 RGBDS (Rednex Game Boy Development System) is a free assembler/linker package
 for the Game Boy and Game Boy Color. It consists of:
@@ -14,54 +12,58 @@ rgbds-linux is a fork of the original RGBDS which aims to make the programs
 more like other UNIX tools.
 
 
-  Installing RGBDS (UNIX)
-=========================
+## Installing RGBDS (UNIX)
 
 RGBDS requires libpng and pkg-config to be installed.
 
 On Mac OS X, install them with [Homebrew](http://brew.sh/). On other Unixes,
 use the built-in package manager.
 
-You can test if they're installed by running "pkg-config --cflags libpng":
+You can test if they're installed by running `pkg-config --cflags libpng`:
 if the output is a path, then you're good, and if it outputs an error then
 you need to install them via a package manager.
 
 To build the programs on a UNIX or UNIX-like system, just run in your terminal:
 
-  make
+```sh
+make
+```
 
 Then to install the compiled programs and manual pages, run (with appropriate
 privileges):
 
-  make install
+```sh
+make install
+```
 
 After installation, you can read the manuals with the man(1) command. E.g.,
 
-  man 1 rgbasm
-
+```sh
+man 1 rgbasm
+```
 
 Note: the variables described below can affect installation behavior when given
 on the make command line. For example, to install rgbds in your home directory
 instead of systemwide, run the following:
 
-  mkdir -p $HOME/{bin,man/man1,man/man7}
-  make install PREFIX=$HOME
+```sh
+mkdir -p $HOME/{bin,man/man1,man/man7}
+make install PREFIX=$HOME
+```
 
+`PREFIX`: Location where RGBDS will be installed. Defaults to /usr/local.
 
-PREFIX: Location where RGBDS will be installed. Defaults to /usr/local.
-
-BINPREFIX: Location where the RGBDS programs will be installed. Defaults
+`BINPREFIX`: Location where the RGBDS programs will be installed. Defaults
 to ${PREFIX}/bin.
 
-MANPREFIX: Location where the RGBDS man pages will be installed. Defaults
+`MANPREFIX`: Location where the RGBDS man pages will be installed. Defaults
 to ${PREFIX}/man.
 
-Q: Whether to quiet the build or not. To make the build more verbose, clear
+`Q`: Whether to quiet the build or not. To make the build more verbose, clear
 this variable. Defaults to @.
 
 
-  Installing RGBDS (Windows)
-============================
+## Installing RGBDS (Windows)
 
 Windows builds are available here: https://github.com/bentley/rgbds/releases