Standardize package names: lower-case, not Mixed_CASE (#2475)

* Rename packages

* Upcasing depends_on() in packages.

* Downcased extends('r')

* Fixed erroneously changed URL that had slipped through.

* Fixed typo

* Fixed link from documentation into package source code.

* Fixed another doc problem.

* Changed underscores to dashes in package names.

* Added test to enforce lowercase, no-underscore naming convention.

* Fix r-xgboost

* Downcase more instances of 'R' in package auto-creation.

* Fix test.

* Converted unit test packages to use dashes not underscores

* Downcase `r` in the docs.

* Update module_file_support.rst

Fix r->R for class R.

var/spack/repos/builtin/packages/uberftp/package.py

@@ -35,7 +35,7 @@ class Uberftp(Package):
     version('2_7', 'faaea2d6e1958c1105cfc9147824e03c')
     version('2_6', '784210976f259f9d19c0798c19778d34')
 
-    depends_on('globus_toolkit')
+    depends_on('globus-toolkit')
 
     def install(self, spec, prefix):
         configure('--prefix={0}'.format(prefix))