* pkgs: refactor needless quoting of homepage meta attribute
A lot of packages are needlessly quoting the homepage meta attribute
(about 1400, 22%), this commit refactors all of those instances.
* pkgs: Fixing some links that were wrongfully unquoted in the previous
commit
* Fixed some instances
Make the existing ghdl recipe more flexible, and introduce "ghdl_llvm"
as a package in addition to "ghdl_mcode". This seems to specifically
require llvm 3.5, though. The flavour is also encoded in the package name.
cc @viric
