Implement zen mode for issues/MRs/notes

Close Zen mode by ESC, foward/backward
Close Zen mode by ESC, foward/backward
Disable buttons if required forms are empty
Fix serialize migration. Fixes #7734
Remove duplicated labels step
update tags count if tag gets deleted
Merge pull request #7738 from dblessing/serialize_migration_fix

Fix serialize migration
Merge pull request #7737 from Razer6/feature/zenmaster

Zen Mode for issues/MR/notes
formatting changes, table->database

Make formatting consistent on page.

Change table -> database as they are database permissions.
add requests link

Add requests link for feature requests.
fail_timeout=0 as recommended by Unicorn

Set's fail_timeout=0 as recommended by
http://unicorn.bogomips.org/Unicorn/Configurator.html#method-i-timeout
when Unicorn is running behind nginx.
set the number of workers to # of cores
Merge pull request #7713 from bbodenmiller/patch-5

Add Feedback link
Merge pull request #7439 from bbodenmiller/patch-6

set the number of workers to # of cores
Merge pull request #7522 from Razer6/fix_tags_count

[UX] Update tag count if tag gets deleted via web interface
Merge pull request #7662 from Razer6/disable_buttons_on_empty_form

[UX] Disable buttons if form is empty
Use the default Unicorn socket backlog value: 1024
Merge pull request #7712 from bbodenmiller/patch-1

set fail_timeout=0 as recommended by Unicorn
Merge branch 'backlog_socket' into 'master'

Use the default Unicorn socket backlog value: 1024

See merge request !1087
Merge pull request #7743 from bbodenmiller/patch-12

formatting changes, table->database