Version-20.06.0: An intermediate release to get the newest improvements into the maxim…

…a windows installer

• Many spell corrections and bugfixes
• Updated Russian translation by OlesyaGerasimenko
• Updated Ukrainian translation by Yuri Chornoivan
• Many corrections to the german translation
• The history sidebar now works again
• TextCells with copy-alt-text caused an crash
• A few additional small bugfixes
• Many (really many!) big stability improvements
• in sqrt(conjugate(f(x))) the horizontal lines coincided
• Strings were searched for comment starts when adding line endings
• Faster start-up by avoiding unneeded redraw events
• A big number of performance improvements
• Unfortunately one last temporary fix reduces performance again
• Corrected a bug that sometimes caused parts of equations not to be displayed
• As this allows to improve performance and stability C++14 is now used
• Speed boost The list of anchors from the manual is now cached on disk