[TxMt] [Xcode Bundle] Bug when running a target

Hello everybody,

I just spent a few hours wrsetling with a strange bug, so I thought I'd let you know.

In run_xcode_target.rb the command for executing shell programs is built in line 295. The environment variables DYLD_FRAMEWORK_PATH and DYLD_LIBRARY_PATH are set. Instead of setting them, the new directories should be appended. In my case this caused some of the libraries I was using to spawn random malloc errors, I guess that is, because macports uses these paths. I don't know what happened exactly, but changing the command to appending the new paths instead of setting them solved my problem and sounds more reasonable anyway.

What do you think,

Cheers, Jonas