docs: updated documentation for directory configuration option

FossilOrigin-Name: 499811b369f6e5ba12bc1ba4d8b71e36ad5ee74cfc1c965d8f33af89bd8093f8

config/nimalyzer.cfg

@@ -109,8 +109,9 @@ source tests/utils/helpers.nim
 # ---------
 # The directory which content will be analyzed. The path must be in Unix form.
 # It will be converted to the proper path by the program. A configuration file
-# mush have at least one source file defined, by 'source', 'files' or
+# must have at least one source file defined, by 'source', 'files' or
 # 'directory' settings. You can add more than one directory setting per file.
+# The program looks in the directory only for files with extensions .nim or .nims.
 # Also, the path can be absolute or relative. In the second form, the path must
 # be relative to the place from which nimalyzer is executed (working directory).
 # The setting below will check all files in directory "src" and its