use sys_open in sys_trytoopenone for Windows ucs2 filenames in abstractions
This properly wraps each call to open/fopen/close using the sys_*
prefixes. This should squash various bugs with non-ASCII characters in Windows filenames.
To merge we need to wrap all open/fopen/close calls in the following directories:
- purr-data/pd/src
- purr-data/pd/extra
- purr-data/externals