OGR provider: deal with wkbUnknown25D (wkbUnknown | wkb25DBit)

This geometry type doesn't exist admitedly in the OGRwkbGeometryType
enumeration but a few OGR drivers can expose layers of this type.
Those layers should be dealt exactly like wkbUnknown layers, i.e.
QGIS should analyze the content to see if there are points, lines,
polygons and create derived layers.

Also report the geometry type of wkbGeometryCollection25D layers in
the U.I.
Remove alias from vector layer if it's an empty string
Apply pull request #1502 provided by bstroebl: Add ntv2 entry for Thuringia
do not transform toString to quote values (NULL integer becomes 0 otherwise)
[FEATURE][composer] Implement an item tree panel for composer windows
(fix #4358). Allows for selection of items, hiding/showing items,
toggling lock status of items and double-clicking to edit item id.
Don't double add features
Fix #10969
[composer] Remove right-click to lock for composer items (fix #5592), now that locked items can be unlocked from the items panel this is no longer required, and frees up right clicks for a composer context menu
[composer] Locked items can't be selected by clicking them in the canvas.
[composer] Deselect items when they are locked from the items panel
[composer] Decrease default snap tolerance to 5 pixels
fix editing of NULL values (fixes 0 to NULL, and fixes setting of NULL values in postgres)
Fixed Legacy date widget default format
[composer] Don't deselect items when unlocking them from the items panel
[composer] Some tweaks to label display name, add display name for legends
[processing] replace str() with unicode() to avoid possible issues with
non-ASCII characters (work in progress)
[processing] fix loading of output rasters with wrong CRS
debian packaging update
Merge pull request #1524 from SrNetoChan/master

Fixed Legacy date widget default format
Fix #10988
Attribute table cache size 0 is represented as "All" in the options
Fix memory leak and pass ownership of py editor widgets to C++