Update to Rodin 3.5 sources

META-INF/MANIFEST.MF

build.gradle

src/org/eventb/core/ast/Formula.java

src/org/eventb/core/ast/FormulaFactory.java

src/org/eventb/core/ast/IAccumulator.java

src/org/eventb/core/ast/ISealedTypeEnvironment.java

src/org/eventb/core/ast/extension/ITypeCheckMediator.java

src/org/eventb/internal/core/ast/FindingAccumulator.java

src/org/eventb/internal/core/ast/Position.java

src/org/eventb/internal/core/parser/BMath.java