-files: could use more power

[Kurper]

I have multiple projects share substantial portions of their codebase (client/, shared/, and server/, basically), and being able to do something like:

sharedfiles.txt:
...

clientfiles.txt:
#include sharedfiles.txt
client.cobra

serverfiles.txt:
#include sharedfiles.txt
server.cobra

would be nice. There are a bunch of ways to fake this with make/msbuild/whatever else you want to use, but it's nice being able to run Cobra with just "cobra -files:files.txt" even for big ol' projects.

[nevdelap]

I haven't tried, but if multiple -files options are/were possible it would be clean simple.

cobra ... -files:sharedfiles.txt -files.clientfiles.txt

[hopscc]

The 'files' option is an accumulator so it will add each filename given to a list and process them in order.