Add a section on using booleans in the scripting language (#44)

* Add a section on using booleans in the scripting language

* Removing statement on SetBlackboard limitations

Author: MasonMcV

docs/guides/scripting.md

@@ -128,6 +128,36 @@ Example:
 val_B = (val_A > 1) ? 42 : 24
 ```
 
+## Boolean Values
+Boolean values can be one of `true` or `false`
+and are saved to the blackboard as `1` and `0` respectively.
+
+Setting booleans:
+```
+val_A = true
+val_B := !false
+```
+The logical `!` works with boolean literals. 
+`!false` is the equivalent of `true`. 
+`val_A` and `val_B` above are equivalent. 
+
+Using booleans:
+```
+<Precondition if="val_A" else="FAILURE">
+<Precondition if="val_A == true" else="FAILURE">
+<Precondition if="val_A == 1" else="FAILURE">
+```
+All of the scripts used in precondition nodes above are valid. 
+
+When evaluating the boolean value, it can be:
+ - checked directly, 
+ - compared with the literals `true` and `false`
+ - compared with `1` and `0`.
+
+
+Note that capitalization of the words "true" and "false" in any manner will not work.
+
+
 ## C++ example
 
 Demonstration of the scripting language, including how to use enums to