#112 New file mapping added as whole file name

[Ryan Wilcox]

To reproduce:

Add/Commit a file to your repository with a "new" file
mapping. The "Add new type" dialog box shows up. Click
anything.

Now go to the file mappings tab in the session
settings. Notice that your new file mapping was added
as the whole name of the file, not just the extention part.

If a file has a period in it, add the (LAST) extention
only. If there is no period, add the whole file name

[Glenn L. Austin]

Logged In: YES
user_id=65082

I'm adding a checkbox that will be enabled and unchecked if there is
a period within the last 30 characters of the filename, or disabled
and checked if a period isn't found.