Generator improvements for using a single .options file

[GoogleCodeExporter]

Describe the requested feature:

- Give an error message if a path to .options is given with -f, but file is not 
found.
- Show the search path for .options when -v is given.
- In addition to normal MessageName.fieldname, match also against 
filename.MessageName.fieldname.

In what situation would the feature be useful:

Sometimes you may want to keep all nanopb-related options in a single file, 
even if you have multiple .proto files. Currently it is possible but has small 
annoyances that would be fixed by these changes.

Original issue reported on code.google.com by Petteri.Aimonen on 17 Jul 2014 at 5:04

[GoogleCodeExporter]

Decided against implementing feature 3, because all message names go into the 
same namespace anyway. Package names should work better instead of filenames 
for distinguishing messages.

Original comment by Petteri.Aimonen on 20 Jul 2014 at 11:18

[GoogleCodeExporter]

This issue was updated by revision 7f97ad549e8e.

Original comment by Petteri.Aimonen on 20 Jul 2014 at 11:57

• Changed state: FixedInGit

[GoogleCodeExporter]

Fix released in nanopb 0.2.9.

Original comment by Petteri.Aimonen on 9 Aug 2014 at 7:28

• Changed state: FixReleased