Add tasks for all the new languages

Task/Test-a-function/Nim/test-a-function-1.nim

@@ -0,0 +1,18 @@
+proc reverse(s): string =
+  result = newString(s.len)
+  for i,c in s:
+    result[s.high - i] = c
+
+proc isPalindrome(s): bool =
+  s == reverse(s)
+
+when isMainModule:
+  assert(isPalindrome(""))
+  assert(isPalindrome("a"))
+  assert(isPalindrome("aa"))
+  assert(not isPalindrome("baa"))
+  assert(isPalindrome("baab"))
+  assert(isPalindrome("ba_ab"))
+  assert(not isPalindrome("ba_ ab"))
+  assert(isPalindrome("ba _ ab"))
+  assert(not isPalindrome("abab"))