Dont clash build files

I tried to create a new project on a folder that already have a project, with it's build.xml and build.properties file. Those original files got overwritten in the process.

To prevent this, I propose using special names for iForce build files. I prefixed "iForce_" to both build files to avoid name clash with possible existing files.

Also, took the chance to move the build files and package file to root directory, remove the SFtemp.zip file, and make the new project process copy those files and generate the data structure instead. This will allow to version those files as well (especially the build.xml file, since new targets may be added for future functionality)