remove rails 5.0 and 5.1 templates

Author: urkle

spec/gemfiles_spec.rb

@@ -3,15 +3,15 @@
 describe SchemaDev::Gemfiles do
 
   it "copies listed files" do
-    config = get_config(ruby: %W[1.9.3 2.1.5], activerecord: %W[5.1 5.2], db: %W[sqlite3 postgresql])
+    config = get_config(ruby: %W[1.9.3 2.1.5], activerecord: %W[5.2 6.0], db: %W[sqlite3 postgresql])
     in_tmpdir do
       expect(SchemaDev::Gemfiles.build(config)).to be_truthy
       expect(relevant_diff(config, "gemfiles")).to be_empty
     end
   end
 
   it "only copies files once" do
-    config = get_config(ruby: %W[1.9.3 2.1.5], activerecord: %W[5.1 5.2], db: %W[sqlite3 postgresql])
+    config = get_config(ruby: %W[1.9.3 2.1.5], activerecord: %W[5.2 6.0], db: %W[sqlite3 postgresql])
     in_tmpdir do
       expect(SchemaDev::Gemfiles.build(config)).to be_truthy
       expect(SchemaDev::Gemfiles.build(config)).to be_falsey