[KDev4] Enabling project setting

[dukju ahn]

Currently, project setting widget such as makebuilder, qmakebuilder
is inactivated. But I've found a clue why it is disabled -- because
the user-specific developerFileUrl doesn't exist in .kdev4/ directory.

If I create developer file under .kdev4/ directory, the project setting
works very well. If I open 2 different projects, one of the two has
developer specific file and the other doesn't have it, the project
setting works only for those project who has developer file.

I set breakpoint on the constructors and methods of ProjectConfigSkeleton,
but the breakpoints didn't work for this class.

I guess projectConfigSkeleton should be fixed, but I'm not sure ATM.