Java type generics (#4832)

* Generify, needs some testing and review

* Remove unnecessary change

* Whoops, ? capture that type

* Misread the docs, whoops

* More permissible arithmetic operations

* Implement believed Optimize generics

* Missed a few generics

* More permissible expr for arrays in parameters

* More permissible expr for bitvecs in parameters

* More permissible expr for bools in parameters

* More permissible expr for fps in parameters

* More permissible expr for fprms in parameters

* More permissible expr for ints in parameters

* More permissible expr for reals in parameters

* Undo breaking name conflict due to type erasure; see notes

* Whoops, fix typing of ReExpr

* Sort corrections for Re, Seq

* More permissible expr for regular expressions in parameters

* Fix name conflict between sequences and regular expressions; see notes

* Minor typo, big implications!

* Make Constructor consistent, associate captured types with other unknown capture types for datatype consistency

* More expressive; outputs of multiple datatype definitions are only known to be sort, not capture, and Constructor.of should make a capture

* Be less dumb and just type it a little differently

* Update examples, make sure to type Expr and FuncDecl sort returns

* General fixups

* Downgrade java version, make it only for the generic support, remove var and Expr[]::new construction

* Turns out Java 8 hadn't figured out how to do stream generics yet. Didn't even show up in my IDE, weird

src/api/java/ArithExpr.java

@@ -20,7 +20,7 @@ package com.microsoft.z3;
 /**
  * Arithmetic expressions (int/real)
  **/
-public class ArithExpr extends Expr
+public class ArithExpr<R extends ArithSort> extends Expr<R>
 {
     /**
      * Constructor for ArithExpr