Add tasks for all the new languages

Task/Roman-numerals-Decode/ERRE/roman-numerals-decode.erre

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+PROGRAM ROMAN2ARAB
+
+DIM R%[7]
+
+PROCEDURE TOARAB(ROMAN$->ANS%)
+      LOCAL I%,J%,P%,N%
+      FOR I%=LEN(ROMAN$) TO 1 STEP -1 DO
+        J%=INSTR("IVXLCDM",MID$(ROMAN$,I%,1))
+        IF J%=0 THEN
+            ANS%=-9999  ! illegal character
+            EXIT PROCEDURE
+        END IF
+        IF J%>=P% THEN
+            N%+=R%[J%]
+          ELSE
+            N%-=R%[J%]
+        END IF
+        P%=J%
+      END FOR
+      ANS%=N%
+END PROCEDURE
+
+BEGIN
+  R%[]=(0,1,5,10,50,100,500,1000)
+  TOARAB("MCMXCIX"->ANS%)         PRINT(ANS%)
+  TOARAB("MMXII"->ANS%)           PRINT(ANS%)
+  TOARAB("MDCLXVI"->ANS%)         PRINT(ANS%)
+  TOARAB("MMMDCCCLXXXVIII"->ANS%) PRINT(ANS%)
+END PROGRAM