Additional command line options

For some reason, mantidworkbench did not have a `--version` option

Also added a command line option to convert warnings to exceptions. This
was used to squash various deprecation warnings that appear when using
newer versions of python libraries.

docs/source/release/v6.1.0/mantidworkbench.rst

@@ -10,6 +10,7 @@ New and Improved
 
 - New plot interactions: Double click a legend to hide it, double click a curve to open it in the plot config dialog.
 - It is now possible to overplot bin data from the matrix workspace view.
+- New command line options ``--version`` will print the version on mantid and exit. ``--error-on-warning`` will convert python warnings into exceptions. This is intended for developers so they can find deprecation warnings more easily.
 - Improved the performance of the table workspace display for large datasets
 - A new empty facility with empty instrument is the default facility now, and
   user has to select their choice of facility (including ISIS) and instrument for the first time

qt/applications/workbench/workbench/app/main.py

@@ -7,12 +7,15 @@
 #  This file is part of the mantid workbench.
 import argparse
 import os
+from mantid import __version__ as mtd_version
+import warnings
 
 
 def main():
     # setup command line arguments
     parser = argparse.ArgumentParser(description='Mantid Workbench')
     parser.add_argument('script', nargs='?')
+    parser.add_argument('--version', action='version', version=mtd_version)
     parser.add_argument('-x',
                         '--execute',
                         action='store_true',
@@ -24,6 +27,10 @@ def main():
     parser.add_argument('--profile',
                         action='store',
                         help='Run workbench with execution profiling. Specify a path for the output file.')
+    parser.add_argument('--error-on-warning',
+                        action='store_true',
+                        help='Convert python warnings to exceptions')
+
     try:
         # set up bash completion as a soft dependency
         import argcomplete
@@ -34,6 +41,10 @@ def main():
     # parse the command line options
     options = parser.parse_args()
 
+    if options.error_on_warning:
+        warnings.simplefilter("error") # Change the filter in this process
+        os.environ["PYTHONWARNINGS"] = "error" # Also affect subprocesses
+
     if options.profile:
         import cProfile
         output_path = os.path.abspath(os.path.expanduser(options.profile))