Asammdf

Fixes
* add itemsDeleted signal to MinimalListWidget
* improve fit and stack for curves containing NaN and inf
* add context menu to MinimalListWidget
* add possibility to load .cfg files in the file widget
* prevent max recursion error in the numeric window

Fixes
* add itemsDeleted signal to MinimalListWidget

Fixes
* fixes 267
* improve keyboard shortcuts handling for the file and plot widgets

Fixes
* use MinimalListWidget for the can database list
* don't load windows if they have no signals
* in Tabular window clear filters that are applied to the index column when toggling the time as date checkbox
* fix missing "found_id_count" error when performing CAN extraction from the GUI
* correctly set the compression argument when performing an export from the GUI
* remove the Search setting from the menu since the search field was removed
* improve alignment in the mdf info tab
* fix CAN extraction of Motorola signals

Standalone GUI builds
* [Linux](https://ci.appveyor.com/project/danielhrisca/asammdf/builds/28932495/job/2ja8ihnrgwncverd/artifacts)
* [Windows](https://ci.appveyor.com/project/danielhrisca/asammdf/builds/28932495/job/ycrenpbs73siw80g/artifacts)

Fixes
* keep the CAN ID as hex in the tabular window (extensible to other bus logging custom fields as well)
* apply new prefix immediately in the tabular window
* use 29bit mask for CAN ID's

Changes
* add to_config method to FileWidget

Standalone GUI builds
* [Linux](https://ci.appveyor.com/project/danielhrisca/asammdf/builds/28879800/job/e4o1mofty9p17xt8/artifacts)
* [Windows](https://ci.appveyor.com/project/danielhrisca/asammdf/builds/28879800/job/cpu52dgfvgl9r9r8/artifacts)

Fixes
* close temporary files in _concatenate_, _to_dataframe_ and _stack_
* correctly set IDBLOCK fields after finalization procedure
* keep CAN ID display as hex values in the tabular window after applying filters
* monkey patch canmatrix.Signal.set_startbit (for handling Motorola signals)
* fix select all and reset channel selection in GUI
* change get_master argument from _one_peace_ to _one_piece_
* do not duplicate dbc files in the CAN export tab
* improve robustness of loading display configuration with computed channels