force rebar to build 'setup' app

There is a bug in exometer/priv/check_packages.script: rebar doesn't build mandatory dependencies of exometer. We can workaround it adding +setup to EXOMETER_PACKAGES environment variable.
mod_signup: remove period from link
mod_authentication: remove period from header
mod_admin: organize less styles in separate files
mod_admin: block menu is right aligned
admin: remove extraneous space
admin: more reordering of less styles
mod_seo: optimize descriptions
admin: fix checkbox in language dropdown
core: make session cookie name configurable (solves problems where old cookies might interfere, especially on Chrome)

(cherry picked from commit d06834ba2a0af409aee154b6526022c3d6278c97)
Make menu_subtree compatible with names
Merge pull request #864 from driebit/fix-menu-subtree-name

Make menu_subtree compatible with names
Remove is_integer check for cc5d94

Otherwise, calling this function with a menu name (e.g., main_menu)
instead of id, will fail.
Merge pull request #865 from driebit/remove-is-int-menu-subtree

Remove is_integer check for cc5d94
mod_search: Use binary parsing of stored query resource

This elimintates the conflict where hasobject/hassubject would use lists
for arguments (e.g. [subject, predicate]), which is a limitation of how
search queries are used in the template system. Two/three-letter queries
stored in resources would break (e.g. hasobject=joy); this is no longer
the case.
core: z_search: fix acl check sql query.

(cherry picked from commit 562ae58a47dd389454cfee0e7c62cbfc7c028b20)
mod_backup: use bullet list for warnings
mod_backup: typo
Merge pull request #857 from Yozhig/master

build: force rebar to build 'setup' app
mod_base: Add JSON source of the Zotonic logo font

For use on https://icomoon.io