Update the version check

Recent versions of setuptools, which includes the pkg_resources module,
return the module name in lowercase. Make the check compatible with both
older and newer versions by comparing the lowercase name. Also, remove
the hardcoded uppercase module name and use `__name__` instead.

Author: azharudd

lnt/lnttool/main.py

@@ -471,15 +471,15 @@ def _version_check():
 
     # Get the current distribution.
     installed_dist = pkg_resources.get_distribution("LNT")
-    if installed_dist.project_name != "LNT" or \
+    if installed_dist.project_name.lower() != lnt.__name__ or \
        pkg_resources.parse_version(installed_dist.version) != \
        pkg_resources.parse_version(lnt.__version__):
         raise SystemExit("""\
 error: installed distribution %s %s is not current (%s %s), you may need to reinstall
 LNT or rerun 'setup.py develop' if using development mode.""" % (
                          installed_dist.project_name,
                          installed_dist.version,
-                         "LNT", lnt.__version__))
+                         lnt.__name__, lnt.__version__))
 
 
 def show_version(ctx, param, value):