Add syntax highlighting in README (#153)

Author: JakeRoggenbuck

README.md

@@ -19,49 +19,62 @@ Objx provides the `objx.Map` type, which is a `map[string]interface{}` that expo
 ### Pattern
 Objx uses a predictable pattern to make access data from within `map[string]interface{}` easy. Call one of the `objx.` functions to create your `objx.Map` to get going:
 
-    m, err := objx.FromJSON(json)
+```go
+m, err := objx.FromJSON(json)
+```
 
 NOTE: Any methods or functions with the `Must` prefix will panic if something goes wrong, the rest will be optimistic and try to figure things out without panicking.
 
 Use `Get` to access the value you're interested in.  You can use dot and array
 notation too:
 
-     m.Get("places[0].latlng")
+```go
+m.Get("places[0].latlng")
+```
 
 Once you have sought the `Value` you're interested in, you can use the `Is*` methods to determine its type.
 
-     if m.Get("code").IsStr() { // Your code... }
+```go
+if m.Get("code").IsStr() { // Your code... }
+```
 
 Or you can just assume the type, and use one of the strong type methods to extract the real value:
 
-    m.Get("code").Int()
+```go
+m.Get("code").Int()
+```
 
 If there's no value there (or if it's the wrong type) then a default value will be returned, or you can be explicit about the default value.
 
-     Get("code").Int(-1)
-
+```go
+Get("code").Int(-1)
+```
 If you're dealing with a slice of data as a value, Objx provides many useful methods for iterating, manipulating and selecting that data.  You can find out more by exploring the index below.
 
 ### Reading data
 A simple example of how to use Objx:
 
-    // Use MustFromJSON to make an objx.Map from some JSON
-    m := objx.MustFromJSON(`{"name": "Mat", "age": 30}`)
+```go
+// Use MustFromJSON to make an objx.Map from some JSON
+m := objx.MustFromJSON(`{"name": "Mat", "age": 30}`)
 
-    // Get the details
-    name := m.Get("name").Str()
-    age := m.Get("age").Int()
+// Get the details
+name := m.Get("name").Str()
+age := m.Get("age").Int()
 
-    // Get their nickname (or use their name if they don't have one)
-    nickname := m.Get("nickname").Str(name)
+// Get their nickname (or use their name if they don't have one)
+nickname := m.Get("nickname").Str(name)
+```
 
 ### Ranging
 Since `objx.Map` is a `map[string]interface{}` you can treat it as such.  For example, to `range` the data, do what you would expect:
 
-    m := objx.MustFromJSON(json)
-    for key, value := range m {
-      // Your code...
-    }
+```go
+m := objx.MustFromJSON(json)
+for key, value := range m {
+  // Your code...
+}
+```
 
 ## Installation
 To install Objx, use go get: