Categorize file list

[Zardoz89]

If a project have many FTL files, a plane list of files could be hard to follow. Categorizing the files by path should help.

For example :

• \foo\bar\lib\globals.ftl
• \foo\bar\lib\lib.ftl
• \foo\bar\components\grid.ftl
• \foo\bar\components\input.ftl

Should generate a file list like this :

lib\
globals.ftl
lib.ftl

components\
grid.ftl
input.ftl

[Zardoz89]

I added some basic support to categorize FTL files using the parent directory. There is room to improve, but it's better that nothing.