Replaces `typedef int32_t TInteger` with a real class

Issue: #51
Adds TInteger::operator +-(int32_t)

With these operators we can write a code like:
  TInteger x = 42;
  int y = x + 2;

Issue: #51
Fixes JIT compilation

Issue: #51
TInteger keeps m_value of type int32_t, not TObject*

Issue: #51
Merge  branch 'refactoring/51/tinteger' into develop

* refactoring/51/tinteger:
  TInteger keeps m_value of type int32_t, not TObject*
  Fixes JIT compilation
  Adds TInteger::operator +-(int32_t)
  Replaces `typedef int32_t TInteger` with a real class

Issue: #51