Removed non-working Module Index link from the main Sphinx docs page

Also:
* Improved Sphinx build options in Makefile and via invoke by adding the following options:
    * -n : nit-picky mode, warn about all missing references
    * -v : increase verbosity (can be repeated)
    * -W : turn warnings into errors
    * -T : show full traceback on exception

1 files changed, 2 insertions, 1 deletions

diff --git a/tasks.py b/tasks.py
index 183a033d..583674e9 100644
--- a/tasks.py
+++ b/tasks.py
@@ -89,11 +89,12 @@ namespace_clean.add_task(tox_clean, 'tox')
 #####
 DOCS_SRCDIR = 'docs'
 DOCS_BUILDDIR = os.path.join('docs', '_build')
+SPHINX_OPTS = '-nvWT'   # Be nitpicky, verbose, and treat warnings as errors
 
 @invoke.task()
 def docs(context, builder='html'):
     "Build documentation using sphinx"
-    cmdline = 'python -msphinx -M {} {} {}'.format(builder, DOCS_SRCDIR, DOCS_BUILDDIR)
+    cmdline = 'python -msphinx -M {} {} {} {}'.format(builder, DOCS_SRCDIR, DOCS_BUILDDIR, SPHINX_OPTS)
     context.run(cmdline)
 namespace.add_task(docs)