nvda

7a33debe - Merge the idea of installing and updating in many places to make code maintenence easier and to simplify possibilities for the user.

Merge the idea of installing and updating in many places to make code maintenence easier and to simplify possibilities for the user. Specifically: * Remove the Updater dialog, instead, always show the Installer dialog, but in the case where a previous copy is installed, note in the caption text that it will be updated, and also set previous defaults for the desktop and logon options. * nvda_slave install now will always try unregistering a previous installation, and if there really was a previous install dir, then also try and remove files mentioned in the old installer log. nvda_slave no longer supports an updateInstall argument. * Split out some install/update code in gui that in future can be used for auto updating.