BUG: Check that the viewer widget still exists when cancelling a hanging protocol download.
BUG: Automatic window/level was not inverted for MONOCHROME1 images. This bug was  introduced in f1b048f. #2075
BUG: Don't assume that a multiframe image has rescale slope and intercept in a functional group sequence. Some modalities don't have rescale values, so we have to wait until a rescale value has been read to be sure that the volume has it. #2078
BUG: Doing a Retrieve&View from the query screen didn't reset the 2D viewers layout, effectively becoming just a Retrieve&Load. To solve this, the current patient is assigned again to the 2D viewer extension when doing a Retrieve&View. #2076
BUG: Previous solution to #2076 in b13539b851 produced a strange effect when applying a hanging protocol, looking like it was applied twice. Now, instead of setting again the patient to the 2D viewer extension, a method of the extension to redo the layout is called.
ENH: Add 0.12.1 fixes to changelog.
ENH: Linguistic fixes to the changelog.
ENH: Version and build ID update (0.12.1, 2014062600)