SGVector::set_const and ::get visible to SWIG again.
To fix failing notebooks.
Merge pull request #2612 from iglesias/develop

SGVector::set_const and ::get visible to SWIG again.
Update documentation in LMNN.cpp.

So that some comments about the implementation do not appear in Doxygen.
Fix mathjax script location in doxygen config files
[ci skip]
Fixed typos in example descriptions
Merge pull request #2615 from sorig/develop

Fixed typos in example descriptions
update the KL notebook
Merge pull request #2613 from yorkerlin/develop

update the KL notebook
Fixed compilation error under Mac OS X
Adjusted condition when TYPE_BOOL is restored
[skip ci]
Fixed macosx ifdef in ProtobufFile
Merge pull request #2621 from lisitsyn/fix/protobuf-macosx

Fixed macosx ifdef in ProtobufFile
better formatting in info message