This adds native macros for subindexes (!level), |see and |seealso
as well as native support for ranges |( |) and pagination format
-- e.g., |textbf -- via the index dialog
Resolves#12478, #7232 and #5014
The feature is complete (incl. tex2lyx) except for
* file format change and lyx2lyx
* docbook/xhtml
* documentation
In particular, the directory frontends/qt4 is renamed to frontends/qt.
Many configurations file have to be updated. All mentions of qt4 in
the source have been audited, and changed to qt if necessary.
The only part that has not been updated is the CMake build system.
