Dropped hard dependency on fastercsv

This is actually an optional dependency that is
not needed for core functionality. Also, lots of
other possible export formats are feasible.
Depending on all these explicitly isn't the way
to go.

Rakefile

@@ -14,7 +14,6 @@ begin
     gem.homepage    = "http://github.com/michael/data_table"
     gem.authors     = ["Michael Aufreiter"]
 
-    gem.add_dependency             'fastercsv', '~> 1.5.3'
     gem.add_development_dependency 'shoulda',   '~> 2.10.3'
 
   end

data_table.gemspec

@@ -44,14 +44,11 @@ Gem::Specification.new do |s|
     s.specification_version = 3
 
     if Gem::Version.new(Gem::RubyGemsVersion) >= Gem::Version.new('1.2.0') then
-      s.add_runtime_dependency(%q<fastercsv>, ["~> 1.5.3"])
       s.add_development_dependency(%q<shoulda>, ["~> 2.10.3"])
     else
-      s.add_dependency(%q<fastercsv>, ["~> 1.5.3"])
       s.add_dependency(%q<shoulda>, ["~> 2.10.3"])
     end
   else
-    s.add_dependency(%q<fastercsv>, ["~> 1.5.3"])
     s.add_dependency(%q<shoulda>, ["~> 2.10.3"])
   end
 end