v0.6.4

Thunderbird 60 release (Linux/Windows)

• Added left click action for libappindicator icon (Thank you for the tip @PlagueCZ, #21)

  This "activate" event needs a specially patched version of libappindicator.
  For openSuSE, you can find it here:

  https://build.opensuse.org/project/show/home:Ximi1970:branches:X11:Unity

  Repositories:
  https://download.opensuse.org/repositories/home:/Ximi1970:/branches:/X11:/Unity/

  The original patch can be found here (for an old version?);
  https://github.com/yuyichao/arch-pkg/blob/facba16172ef6caa7fddd1babb21a9d2d5137f32/pkg/all/libappindicator/activate.patch

  My modfied version here:
  https://build.opensuse.org/package/view_file/home:Ximi1970:branches:X11:Unity/libappindicator/libappindicator-activate-support.patch?expand=1