Misc. changes to installer including:

Misc. changes to installer including:

1 - Fix profile manager links
2 - Add tag at top (currently "Trunk") for easy changing
3 - Add optional extras.nsi for easy additions of extra install/uninstall lines
4 - Run uninstaller if installing to a directory with one (old style OR new style)
5 - Allow license override and only show license page if one defined
    Ex. With NSIS_EXTRAOPTS set to "-DPRODUCT_LICENSE=some/path"
    Or to disable use "-DPRODUCT_LICENSE"
6 - Similar to devbuild, allow for registration per-machine by default
    This includes needing to not wipe out the folder this is stored in
7 - Make "Everyone" able to write to the install folder when:
    Autoupdate is an option
    Per-machine registration is an option
8 - Make silent uninstall function

Signed-off-by: Thomas Berezansky <tsbere@mvlc.org>