Merge gwyddion 2.28 (universe) from Debian unstable (main)

[Nicola Ferralis]

Gwyddion 2.28 has been release upstream and in Debian unstable. It includes support for new file. The thumbnailer is now correctly packaged. Changelog below:

Modules
    Nanoscantech (new): Imports NanoScanTech .nstdat files.
    TIA SER (new): Imports FEI Tecnai imaging and analysis .ser files.
    DM3 (new): Imports Digital Micrograph DM3 TEM images (only greyscale data at present).
    PID (new): Simple simulation of PID loop effects during scanning.
    Lateral force (new): Simulation of lateral force from topography channel.
    Neural network (new): Neural network data processing.
    XY denoise (new): Data denoising based on horizontal and vertical scans.
    WIP: Spectral transformation for Raman data was fixed and swapped XY axes in datafields were really fixed.
    Zeiss: Files without key-value pairs in tag 34118 are recognised and loaded.

Other

    Compatibility with libpng 1.5 was corrected.
    GNOME 3 thumbnailer file is installed, making gwyddion-thumbnailer work automatically in GNOME 3.
    configure has an option --enable-home-installation to ease desktop integration if you compile from source code and install to your home.

[Nicola Ferralis (feranick)]

Debdiff attached.