init: complete existing files on Tcsh completion

Fixes #523

Author: xdelaruelle

NEWS.rst

@@ -151,6 +151,8 @@ Modules 5.4.0 (not yet released)
 * Add ``--ignore`` option to :mfcmd:`source-sh` modulefile command to define
   shell elements changed by shell script that should be ignored. (fix issue
   #503)
+* Init: Improve Tcsh shell completion script to complete against existing
+  files when pattern starts with ``/``, ``.`` or ``~/``. (fix issue #523)
 
 
 .. _5.3 release notes:

init/tcsh_completion.in

@@ -29,7 +29,8 @@ alias _module_not_yet_loaded '\\
 
 alias _module_modulepath 'echo ${MODULEPATH} | sed '"'"'s/:/\n/g;'"'"' '
 
-complete module 'n/help/`_module_avail`/' \
+complete module 'C,/*,f,' 'C,.*,f,' 'C,~/*,f,' \
+        'n/help/`_module_avail`/' \
         'n/add/`_module_not_yet_loaded; echo "@comp_load_opts@"`/' \
         'n/load/`_module_not_yet_loaded; echo "@comp_load_opts@"`/' \
         'n/add-any/`_module_not_yet_loaded; echo "@comp_load_opts@"`/' \