reorganize ini file

There is now a new category "galaxy". Please delete old ini file.
No new settings.
Also make sure that all possible settings in ini file
are written into it by default so that one can know about them
without browsing the code.
reorganize settings dialog accordingly and add UI setters

for expansion speed and nearby systems
"MINORS" and "RESEARCHSPEED" are the only ones without UI setter
nearby systems and expansion speed cannot be changed after game start