Use unix-style line endings on OSX.

This is what later versions of QScintilla as CR is a pre-OSX thing.
Refs #10654
Merge pull request #110 from mantidproject/bugfix/10654_osx_script_editor_eol

Use unix-style line endings in script editor on OSX.
Merge remote-tracking branch 'origin/feature/10771_usage_url_fixed'
Merge pull request #113 from mantidproject/feature/10838_suppress_osx_warnings

Refs #10838. Suppress new clang warnings. Fix remaining warning.
Merge remote-tracking branch 'origin/bugfix/10400_script_editor_uneditable'
Merge remote-tracking branch 'origin/bugfix/10829_MDNormDirectSC_help'
Merge remote-tracking branch 'origin/bugfix/10819_zoom_issue'
Merge pull request #112 from mantidproject/bugfix/10820_fix_convert

Bugfix/10820 fix convert
Set the correct permissions on installed Python files.

Refs #10825
Merge branch 'feature/10825_bundle_ipython_notebook' into develop