This commit adds a way to set some default visual settings for each
acquision mode. This allows to hide/show specific columns of the table.

This commit add the loading and saving of export algorithm list in the
rundex file.

This commit adds a setting in the configuration to set the default
output file extension for each export algorithm.

The configuration contains a list of export algorithm per acquisition
mode.

This commit adds the support for SANSILLParameterScan algorithm for D16
instrument in DrILL.

Global settings are now a list of keys and the values are taken from the
algorithm.

To fit with the algorithm, the default values of MaxQxy and DeltaQ have
been changed.

OutputPanels options was missing from the DrILL interface.

The D20 instrument, associated technique, acquisiton mode and options
have been added to the configuration file of DrILL interface.

The D2B instrument, associated technique, acquisiton mode and options
have been added to the configuration file of DrILL interface.

The WedgeWorkspace parameter is now useless in SANSILLAutoProcess. The
name is created from the output workspace name.

The parameter is also removed from the DrILL interface.

This commit removes the locking context defined in
08da46b5. The SANS ILL auto processing
is not thread safe anymore. This will avoid potential dead locks.
The max number of threads is set to 1 for SANS in the DrILL interface
configuration file.

Set back the default option of DirectFlatBackground for reflectometry.
It will change to 'Background Average' when the correponding PR is
merged.

Flags are now defined for the acquisition modes. They represent
parameters that will not be added to the table or the settings. For now,
it is only used by the reflectometry algorithm that needs a flag
specifying the type of acquisition (polarized or not).

Order of columns has been changed to be more consistent between
polarized and unpolarized reflectometry.

The 'Run' parameter is only valid for unpolarized reflectometry.

Omega scan acquisition mode is not yet supported by the DrILL interface.

The specifications define a new dictionary that contains the maximum
number of threads that each algorithm should use. If no value is
provided for an algorithm, the thread pool will use the idel number of
threads from Qt (QThread::idealThreadCount()).

SampleThickness is now in the table *and* in the global settings. A
default value is then provided by the global settings and the user can
override it through the table (without the need to populate the
CustomOptions).