Update README.md

README.md

@@ -6,3 +6,44 @@
 [![Build Status](https://travis-ci.org/JuliaIO/IniFile.jl.svg?branch=master)](https://travis-ci.org/JuliaIO/IniFile.jl)
 
 Reading and writing Windows-style INI files from Julia
+
+## Usage
+
+```julia
+Pkg.add("IniFile") # first-time only
+using Inifile # load code into current session
+```
+
+#### Create IniFile
+```julia
+ini = IniFile()
+```
+
+#### Get defaults & sections of an IniFile
+```julia
+sections(ini)
+defaults(ini)
+```
+
+#### Get specific key from section, return `default` if not found
+```julia
+get(ini, "section", "key", default)
+```
+
+#### Set key for section
+```julia
+set(ini, "section", "key", value)
+```
+
+#### Parse a `*.ini` file
+```julia
+ini = read(IniFile(), "file.ini")
+```
+
+#### Write out a `*.ini` file
+```julia
+open("file.ini", "w+") do io
+    write(io, ini)
+end
+```
+