Add tasks for all the new languages

Task/Run-length-encoding/Phix/run-length-encoding.phix

@@ -0,0 +1,30 @@
+function encode(sequence s)
+sequence out = {}
+integer prev_char,count = 1
+    if length(s) then
+        prev_char = s[1]
+        for i=2 to length(s) do
+            if s[i]!=prev_char then
+                out &= {count,prev_char}
+                prev_char = s[i]
+                count = 1
+            else
+                count += 1
+            end if
+        end for
+        out &= {count,prev_char}
+    end if
+    return out
+end function
+
+function decode(sequence s)
+sequence out = {}
+    for i=1 to length(s) by 2 do
+        out &= repeat(s[i+1],s[i])
+    end for
+    return out
+end function
+
+sequence s = encode("WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW")
+pp(s)
+?decode(s)