Add tasks for all the new languages

Task/Arithmetic-Integer/Nim/arithmetic-integer.nim

@@ -0,0 +1,22 @@
+import parseopt,strutils
+
+var
+  opt: TOptParser = initOptParser()
+  str = opt.cmdLineRest.split
+  a: int = 0
+  b: int = 0
+
+try:
+  a = parseInt(str[0])
+  b = parseInt(str[1])
+except EinvalidValue:
+  quit("Invalid params. Two integers are expected.")
+
+
+echo ("a      : " & $a)
+echo ("b      : " & $b)
+echo ("a + b  : " & $(a+b))
+echo ("a - b  : " & $(a-b))
+echo ("a * b  : " & $(a*b))
+echo ("a div b: " & $(a div b))
+echo ("a mod b: " & $(a mod b))