[orx-expression-evaluator] Switch to antlr-kotlin for parser generation and make it a common kotlin module

orx-expression-evaluator/README.md

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+# orx-expression-evaluator
+
+Tools to evaluate strings containing mathematical expressions.
+
+# Expression evaluator
+
+```kotlin
+val expression = "x + y"
+val constants = mapOf("x" to 1.0, "y" to 2.0)
+evaluateExpression(expression, constants)
+```
+## Built-in expression functions
+
+Unary functions:
+ * `abs(x)`
+ * `acos(x)`
+ * `asin(x)`
+ * `atan(x)`
+ * `ceil(x)`
+ * `cos(x)`
+ * `degrees(x)`
+ * `exps(x)`
+ * `floor(x)`
+ * `radians(x)`
+ * `round(x)`
+ * `saturate(x)`, clamp x to [0.0, 1.0]
+ * `sqrt(x)`
+ * `tan(x)`
+
+Binary functions:
+ * `atan2(x, y)`
+ * `length(x, y)`, the Euclidean length of the vector (x,y)
+ * `max(x, y)`,
+ * `min(x, y)`,
+ * `pow(x, n)`
+ * `random(x, y)`, return a random number in [x, y)
+ 
+Ternary functions:
+ * `length(x, y, z)`, the Euclidean length of the vector (x, y, z)
+ * `max(x, y, z)`
+ * `min(x, y, z)`
+ * `mix(l, r, f)`
+ * `smoothstep(e0, e1, x)`
+ * `sum(x, y, z)`
+
+Quaternary functions:
+* `length(x, y, z, w)`, the Euclidean length of the vector (x, y, z)
+* `max(a, b, c, d)`
+* `min(a, b, c, d)`
+* `sum(a, b, c, d)`
+
+Quinary functions:
+* `map(x0, x1, y0, y1, v)`
+* `max(a, b, c, d, e)`
+* `min(a, b, c, d, e)`
+* `sum(a, b, c, d, e)`
+
+# Compiled functions
+
+```kotlin
+val expression = "x * 5.0 + cos(x)"
+val f = compileFunction1(expression, "x")
+f(0.0)
+```
+
+```kotlin
+val expression = "x * 5.0 + cos(x) * y"
+val f = compileFunction2(expression, "x", "y")
+f(0.0, 0.4)
+```
+
+# Property delegates
+
+```kotlin
+val constants = mutableMapOf("width" to 300.0)
+val settings = object {
+    var xExpression = "cos(t) * 50.0 + width / 2.0"
+}
+val xFunction by watchingExpression1(settings::xExpression, "t", constants)
+
+xFunction(1.0)
+```
+<!-- __demos__ -->
+## Demos
+### DemoExpressionEvaluator01
+[source code](src/demo/kotlin/DemoExpressionEvaluator01.kt)
+
+![DemoExpressionEvaluator01Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-expression-evaluator/images/DemoExpressionEvaluator01Kt.png)
+
+### DemoExpressionEvaluator02
+[source code](src/demo/kotlin/DemoExpressionEvaluator02.kt)
+
+![DemoExpressionEvaluator02Kt](https://raw.githubusercontent.com/openrndr/orx/media/orx-jvm/orx-expression-evaluator/images/DemoExpressionEvaluator02Kt.png)