[DAPHNE-#357] typeOf() function to determine the type of an object

[Garic152]

This PR implements https://github.com/daphne-eu/daphne/issues/357 and allows the user to determine the type of a Scalar or Object in DAPHNE DSL-Scrips using the typeOf() built-in function.

Features:

• typeOf(scalar): Returns the C++ representation of the scalar value type using ValueTypeUtils.h.
• typeOf(object): Returns the dimension and ValueType of an object as (dim, scalarType).

Changes:

• Added the typeOf() DaphneDSL built-in function, the typeOf DaphneIR operation, as well as the typeOf() kernel
• Added corresponding script-level tests as a new test file TypeOfTest.cpp in .../cli/operations, ensuring that the correct types get printed for scalar types and both sparse and dense matrices

[Garic152]

Thank you for reviewing the code, I totally overlooked the fact that the frames were able to contain multiple value types. I changed the typeOf(frame) kernel to now iterate over the columns of the frame and return the result formatted like the print() function. I also adjusted the existing tests and added another line testing the newly added functionality with all supported types in one frame.

Let me know if there are still some things missing and I'll add them as soon as possible!

[AlexRTer]

Thank you for implementing all requested changes and in such a short time frame as well. From my point of view, this PR is ready to be merged.