Remove evil "sec:" prefix from some \label markups; this is bad for

filenames on Windows (& Mac?) platforms.

Doc/inst/inst.tex

@@ -723,7 +723,7 @@ apply, values from ``earlier'' files are overridden by ``later'' files.
 
 
 \subsection{Location and names of config files}
-\label{sec:config-filenames}
+\label{config-filenames}
 
 The names and locations of the configuration files vary slightly across
 platforms.  On \UNIX, the three configuration files (in the order they
@@ -787,7 +787,7 @@ And on MacOS, they are:
 
 
 \subsection{Syntax of config files}
-\label{sec:config-syntax}
+\label{config-syntax}
 
 The Distutils configuration files all have the same syntax.  The config
 files are grouped into sections; there is one section for each Distutils