Open files from /assets (i.e. read-only) even if asked for write access
Open files from /assets (i.e. read-only) even if asked for write access

It seems to work better to silently "open" a such file read-only even if write
access is requested, and let write attempts, if any, fail later. Otherwise
loading a document from /assets fails with that idiotic "General Error"
dialog...

Change-Id: I95cbe18010ec5e75ee5993faef2656ae8a2f981b

JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core,JurassicWordExcel/core