We can look at the PushCommits object to see how many commits were
included in a commit, and add some template logic to only show the
comparison link when there are at least 2 commits in a push. We also
correct the link to display the number of commits.

We have new tab, but we had no entry. That's why it was showing "code"
(lowercase) as this is text id, where we were expecting properly title cased
"Code" to be shown in English version.

Also add Polish translation "code=Kod".

Just some phrasing changes to make the English translations sound more natural.

Consider following LDAP search query example:

    (&(objectClass=Person)(|(uid=%s)(mail=%s)))

Right now on first login attempt Gogs will use the text supplied on login form
as the newly created user name. In example query above the text matches against
both e-mail or user name. So if user puts the e-mail then the new Gogs user
name will be e-mail which may be undesired.

Using optional user name attribute setting we can explicitly say we want Gogs
user name to be certain LDAP attribute eg. `uid`, so even user will use e-mail
to login 1st time, the new account will receive correct user name.

The hyperlink and the display name of the branch if the branch is in a folder or the branch name has '#'

- copy link button: #1396, #1168, #1668,
- synxtax highlight: #1712, #1549, #1315, #670
- z-index: #1942