don't copy .files into the SSG output dir

they may be vim swap files and that kind of garbage

Signed-off-by: Brian S. Stephan <bss@incorporeal.org>

incorporealcms/ssg.py

@@ -97,6 +97,9 @@ class StaticSiteGenerator(object):
 
             # process and copy files
             for file_ in files:
+                if file_[0] == '.':
+                    cprint(f"skipping {file_}", 'yellow')
+                    continue
                 self.build_file_in_destination(source_dir, base_dir, file_, dest_dir, convert_markdown)
 
     def build_subdir_in_destination(self, source_dir: str, base_dir: str, subdir: str, dest_dir: str) -> None: