Fix for issue #1113: file paths with spaces passed incorrectly as javac arguments on Windows

The bug is from a commit from Feb 6 which changes how the classpath is passed to javac as @argfiles parameter.

SHA-1: 3867d4d17ce7785e83db1b1f1e8dc67f5074d251

According to the [javac specification](http://docs.oracle.com/javase/6/docs/technotes/tools/windows/javac.html):

> An argument file can include javac options and source filenames in any combination. The arguments within a file can be space-separated or newline-separated. If a filename contains embedded spaces, put the whole filename in double quotes, and double each backslash ("My Files\\\\Stuff.java").