Win32 dependencies

[Phil Longstaff]

I'm currently trying to build a more up-to-date version of webkit for win32, hoping that some of the bugs that are affecting gnucash (showing images on an invoice, print font size) have been fixed.

I will also tackle pre-building some of the dependencies and zipping up the file so that we don't need to rebuild them.  Derek, I assume you would like them on sourceforge, not gnucash.org.  How should we handle versioning?

My proposal is to set up a dependencies folder.  Under it, a set of folders, one per dependency (webkit, libxml, ...).  When I build a dependency, I'll zip it up as dependency_version_win32.zip (e.g. webkit_1.1.13_win32.zip) and put it into the webkit dependency folder.

Phil