submodules: Updated eventrecorder
submodules: updated eventcapture
Fix image stack import.

In #761, the signal for addStack was changed to have signature
pyqtSignal(int), where the parameter indicates the lane number for the
new stack. New lanes are encoded with -1 instead of None.

This patch adjusts the addStack() function to handle laneIndex == -1 to
indicate a new lane.
submodules: Updated eventcapture
ilastik.py: Fixed typo in shell debugging arg name.
submodules: updated eventcapture
tests: Removed all old recorded test cases, and replaced them with newly recorded versions.
AddFileButton: Tweaked option text for clarity.
submodules: updated eventcapture
Ensure that submodule discovery works even if ilastik is accessed via a symbolic link
submodules: If the submodule directory isn't found, ignore the error and just skip submodule discovery.
setup_mac.py: Exclude cplex libraries from the build unless --include-cplex is specified.
OpDataSelection: By default, assume a drange of (0,255) for all uint8 images (can still be overridden by the user).
Fixes #797
DataSelection: When a new file is added to any role, show the newly added dataset.
Fixes #796
tests: counting: Relaxed an assertion constraint
tests: Optionally skip gui tests with an env variable SKIP_GUI_TESTS=1
Added bin/labelcounts.py: A little utilily for printing the user label histogram for an .ilp
import cleanups
shell: In debug mode, open the main window at consistent startup coordinates.
shell: Buttons for new projects have unique objectNames