(commons) Remove useless static class Constants

Replace its methods by equivalents #define
(Doxygen) Documents more methods
(misc) Always deal with / separators, instead of native ones
(gui) Auto select the linked default result when selecting a library entry
Minor fixes
(gui) Align track picture in center of display area
(patterns) Fix label sql index
(rename) Many improvements
(search) Pattern improvements
(gui) Fix tracks informations displaying