Cleaning up git submodules

I have a mess of submodules. Cleaning these up:

- Removing libwpd from root
- Removing wordptr from root
- Updating .gitmodules with new repositories
Complete submodule cleanup

Added wordptr, libwpd and tegen submodules to source/downloads/code
Improve linux daemon posts; update prep-gists.sh

- Due to the submodule revisions, update prep-gists.sh
- Added additional references to linux daemon post
- Reorganized URL references in some files