realsense: check hand is tracked

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37641 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Actually allow round(a,b) in input bar

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37642 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Changing javagiac.dll's to the latest version in desktop/kickstart.xml

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37643 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
Changing giac.js to the latest version in web/kickstart.xml

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37644 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e
realsense: can use also 2D mouse

git-svn-id: http://dev.geogebra.org/svn/trunk/geogebra@37645 23ce0884-8a58-47d3-bc5c-ddf1cd5b9f9e