renamed some filenames to not end with a period

Windows does not allow such filenames, which prevented cloning git-annex
on windows.

doc/bugs/Error_cloning_repository_on_Windows.mdwn

@@ -16,3 +16,5 @@ Because of this, developing and building on Windows is harder and more needlessl
 ### What steps will reproduce the problem?
 
 Cloning the git-annex repository on Windows 7 — or any other Windows, I believe.
+
+> [[fixed|done]] --[[Joey]]

doc/bugs/Error_cloning_repository_on_Windows/comment_1_3c95fbb637e8043f988822069518fd3a._comment

@@ -0,0 +1,9 @@
+[[!comment format=mdwn
+ username="joey"
+ subject="""comment 1"""
+ date="2020-10-07T16:11:23Z"
+ content="""
+Thanks for reporting that. We used to have problems with : getting into
+filenames in the website, fixed that, so I've gone ahead and fixed this
+too, including (I hope) configuring it to reject a trailing period.
+"""]]