Added build files to turn the bible into a book

manuscript/chapter10.txt

@@ -0,0 +1,31 @@
+# Arithmetic
+
+## Simpler syntax to set variables
+
+```shell
+# Simple math
+((var=1+2))
+
+# Decrement/Increment variable
+((var++))
+((var--))
+((var+=1))
+((var-=1))
+
+# Using variables
+((var=var2*arr[2]))
+```
+
+## Ternary tests
+
+```shell
+# Set the value of var to var2 if var2 is greater than var.
+# var: variable to set.
+# var2>var: Condition to test.
+# ?var2: If the test succeeds.
+# :var: If the test fails.
+((var=var2>var?var2:var))
+```
+
+<!-- CHAPTER END -->
+