Improve wording in docs

doc/vcsh.1.ronn

@@ -101,7 +101,7 @@ an interactive user.
   Set up repository with recommended settings.
 
 * which <substring>:
-  Find <substring> in any tracked file name.
+  Find <substring> in name of any tracked file.
 
 * write-gitignore:
   Write .gitignore.d/<repo> via git ls-files.

vcsh

@@ -35,7 +35,7 @@ help() {
    run <repo> \\
        <command>        Use this repository
    setup                Set up repository with recommended settings
-   which <substring>    Find substring in any tracked file name
+   which <substring>    Find substring in name of any tracked file
    write-gitignore \\
    <repo>               Write .gitignore.d/<repo> via git ls-files