Pass in parameters to go build AFTER the output parameter

See: http://golang.org/cmd/go/#hdr-Compile_packages_and_dependencies
Use the folder as package name for new files
In new projects, create a main package

In go projects, it is not allowed to place any source inside
the src/ directory. Now a main package is created and the go-file
will be placed there
Added new function to determine the package of a file
Set the working directory when running go build
Always build the whole pkg with go build instead of a single file
Merge pull request #666 from d3xter/build_package

Build package instead of single file