Made Point, Interval, Boundary and Dataset classes use generic element type, ELEM_TYPE, instead of hard-coded Real. The default ELEM_TYPE if not specified is Real.
Made all structures use generic ELEM_TYPE instead of Real.
Removed default element type (Real). A point's element's type must now be specified explicitly.
Wrapped all test-specific symbols in anonymous namespace and made static. Also prevented any line from exceeding 79 characters.