Fix error in a handful of recipes caused by upgrade to mechanize 0.3 which returns lists instead of iterators for forms() and links()

Fixes #1698646 [Failed: Fetch news from New York Times](https://bugs.launchpad.net/calibre/+bug/1698646)

recipes/espn.recipe

@@ -86,7 +86,7 @@ class ESPN(BasicNewsRecipe):
                     f.write(raw)
                 br.open_local_file(fname)
 
-            br.form = br.forms().next()
+            br.form = list(br.forms())[0]
             br.form.find_control(
                 name='username', type='text').value = self.username
             br.form['password'] = self.password

recipes/folhadesaopaulo_sub.recipe

@@ -89,7 +89,7 @@ img { background: none !important; float: none; margin: 0px; }
         br = BasicNewsRecipe.get_browser(self)
         if self.username is not None and self.password is not None:
             br.open('https://acesso.uol.com.br/login.html')
-            br.form = br.forms().next()
+            br.form = list(br.forms())[0]
             br['user'] = self.username
             br['pass'] = self.password
             br.submit().read()

recipes/nikkei_news.recipe

@@ -51,8 +51,8 @@ class NikkeiNet_paper_subscription(BasicNewsRecipe):
             br.open('http://www.nikkei.com/')
             print "-------------------------open first login form-----------------------------"
             try:
-                url = br.links(
-                    url_regex="www.nikkei.com/etc/accounts/login").next().url
+                url = list(br.links(
+                    url_regex="www.nikkei.com/etc/accounts/login"))[0].url
             except StopIteration:
                 url = 'http://www.nikkei.com/etc/accounts/login?dps=3&pageflag=top&url=http%3A%2F%2Fwww.nikkei.com%2F'
             br.open(url)  # br.follow_link(link)

recipes/nytimes_sub.recipe

@@ -417,7 +417,7 @@ class NYTimes(BasicNewsRecipe):
         br = BasicNewsRecipe.get_browser(self)
         if self.username is not None and self.password is not None:
             br.open('https://www.nytimes.com/auth/login')
-            br.form = br.forms().next()
+            br.form = list(br.forms())[0]
             br['userid'] = self.username
             br['password'] = self.password
             br.submit().read()