Created Polyglot compatibility (markdown)

Polyglot-compatibility.md

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+# Groovy compatibility
+
+## Isn't ANY Java library compatible with Groovy?
+
+  Yes, of course. You can use j8583 in Groovy just as you would use any other Java library. However,
+  some j8583 classes have certain methods in them written specifically for usage within Groovy.
+
+### j8583 short-hand in Groovy
+
+  In Java, you can deal with values in an IsoMessage like this:
+
+```java
+message.setValue(32, "Some value", IsoType.LLVAR, 0);
+IsoValue isoValue = message.getField(32);
+String value = (String)message.getObjectValue(32);
+Object value2 = message.getField(32).getValue();
+```
+
+  In Groovy you can do the same like this
+
+```groovy
+message[32] = IsoType.LLVAR("Some value")
+message[7] = IsoType.DATE10(new Date())
+message[41] = IsoType.ALPHA("Term", 16)
+message[11] = IsoType.NUMERIC(123, 6)
+IsoValue isoValue = message[32]
+def value = message[32]?.value
+```
+
+  This is because the `IsoMessage` class has get `getAt()` and `putAt()` methods that work similar
+  to `getField()` and `setField`, and the `IsoType` class has two `call()` methods, with and without
+  length, which return `IsoValue` instances with the proper type and length. The variant that has a length parameter
+  must be used with NUMERIC and ALPHA types, and the other types can use the variant without length.
+
+# Scala compatibility
+
+  In a similar fashion, you can use a shorter notation in Scala to set and get fields:
+
+```scala
+message(32) = IsoType.LLVAR("Some value")
+message(7) = IsoType.DATE10(new Date())
+message(41) = IsoType.ALPHA("Term", 16)
+message(11) = IsoType.NUMERIC(123, 6)
+val v1:String = message(32).getValue
+val v2:String = message.getObjectValue(32)
+```
+
+  This is because IsoMessage also implements the `apply()` and `update()` methods that work similarly to `getField()` and `setField()`. Also, `IsoType` now implements `apply()` so that you can create IsoValues from IsoTypes.
+
+### Builder Pattern
+
+  In any language, you can use the builder pattern, since now the `setValue` and `setField` methods return the message itself:
+
+```java
+message.setValue(4, amount, IsoType.AMOUNT, 12)
+  .setValue(7, new Date(), IsoType.DATE, 10)
+  .setValue(11, trace, IsoType.NUMERIC, 6);
+```
+
+  Of course it can be more succint in Groovy or Scala:
+
+```groovy
+message.setField(4, IsoType.AMOUNT(amount))
+  .setField(7, IsoType.DATE(new Date()))
+  .setField(11, IsoType.NUMERIC(trace, 6))
+```