Fixes needed to build htop (#3691)

* Fixes needed to build htop

* Build libncursesw.so, not libncurses.so

* Remove htop hack now that it is picking up newer ncurses

* Tell packages to link to new ncursesw libraries

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

@@ -45,4 +45,4 @@ class Readline(AutotoolsPackage):
     patch('readline-6.3-upstream_fixes-1.patch', when='@6.3')
 
     def build(self, spec, prefix):
-        make('SHLIB_LIBS=-lncurses')
+        make('SHLIB_LIBS=-lncursesw')