Username database field length does not match HTML text input maxlength

[niallkennedy]

The user_login column in $wpdb->users is defined as a variable character field of up to 60 characters. The text input field in wp-signup referencing the same column has a maxlength attribute set to 50. Values should match.

Patch to specify user_login maxlength as 60, not 50.

[niallkennedy]

Set maxlength of user_login to 60 to match database value.

[wpmuguru]

(In [15217]) signup username length consistent with user_login field, props niallkennedy, fixes #13842