Added detailed description to the C++ RM

[bmribler]

• Added c++ source files to file patterns to include detailed description of member functions.
• Cleaned up many outdated comments and added missing documentation of several parameters.
• Removed the C++ API main page for it's no longer relevant because the C++ documentation is now in the RM of the main library documentation.

Fixes #5529

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Important

Added C++ source files to FILE_PATTERNS in Doxyfile.in for detailed member function descriptions.

• Configuration:
  • Added @HDF5_CPP_SRC_DIR@/*.h and @HDF5_CPP_SRC_DIR@/*.cpp to FILE_PATTERNS in Doxyfile.in to include C++ source files for detailed member function descriptions.

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[brtnfld]

Didn't you lose the introductory material when you deleted the file? Why is that no longer important?

[brtnfld]

The CXX/TUTR aren't referenced from anywhere

[bmribler]

Didn't you lose the introductory material when you deleted the file? Why is that no longer important?

Actually, when the C++ RM was moved to doxygen, it already lost that introduction. The C++ RM was put in as part of the main RM, so my objection about losing the introduction wasn't valid. The C++ RM even lost all the detail description of the methods, hence issue #5529. This PR fixes #5529, but there is no good place to add the introduction back in the current structure.

[bmribler]

The CXX/TUTR aren't referenced from anywhere

The only way to get to the C++ API is in the Reference Manual.