update some eclipse files
generic types are now allowed everywhere anyway
fix casting errors
make interpretation judgment more general
allow declaration of internal funcs and procs
unify ExactMatrixType and GenericMatrixType
remove no longer necessary casts
remove distinction of Exact- and GenericMatrixType

A MatrixType can now be exact, generic or mixed. When dealing
with such a type, always use the SmartMatrixType class which
implements equals() and can detect if it is generic, exact or
mixed.
generic func return types must be defined in the parameters
fix variable declaration typing
small change in SmartMatrixType
fix variable typing again
variable declarations: can only declare generic types where they are defined
merge core project in linear.algebra.matrix
fix VariableRegister to handle superScope == null
subtyping of matrices: accept any MatrixType instances
validate generic matrix parameters

Make sure a function call has a valid configuration of parameter
types. Use them to type the return value if it is generic.
allow generic type declarations in procs, too
allow returns only in func declarations
returns must have the correct type