Some directories had a capital in their name [fixed]. Added a recursive factorial algorithm. (#763)

* Renaming directories
* Adding a recursive factorial algorithm

maths/abs.py

@@ -0,0 +1,18 @@
+def absVal(num):
+    """
+    Function to fins absolute value of numbers.
+    >>absVal(-5)
+    5
+    >>absVal(0)
+    0
+    """
+    if num < 0:
+        return -num
+    else:
+        return num
+
+def main():
+    print(absVal(-34)) # = 34
+
+if __name__ == '__main__':
+    main()