Use new installer feature from packager.io

Postinstall for openproject is now in its own addon at https://github.com/pkgr/addon-openproject.

Conflicts:

	.pkgr.yml
Add addon-legacy-installer
Removal of builpack entry
Add ruby 2.3.1 to setup
add rake tasks for mysql db backups/restores
postgresql db backups
add specs for backup task
whitespace fixes and other minor things
only sanitize_filename the actual filename
do not use the PGPASSFILE if no password is provided
db backup filename depends on db adapter
pg_dump needs the database name as the last param
Add /backup to .gitignore
Merge pull request #2082 from opf/feature/backup_task_3-0

rake task to backup and restore the database
Merge pull request #2076 from opf/feature/packager-new-installer-stable

Use new packager installer
dead code removal
Merge pull request #2111 from opf/fix/dead_code_removal

dead code removal
update rails to 3.2.20

This is a security fix against a file existence exposure CVE-2014-7819

see:
http://weblog.rubyonrails.org/2014/10/30/Rails_3_2_20_4_0_11_4_1_7_and_4_2_0_beta3_have_been_released/

Conflicts:
	Gemfile.lock
Fix sprockets file exposure vulnerability

There is an information leak vulnerability in Sprockets. This
vulnerability
has been assigned the CVE identifier CVE-2014-7819.

see:
https://groups.google.com/forum/#!topic/rubyonrails-security/wQBeGXqGs3E

The patch given in
https://15028051456732132684.googlegroups.com/attach/7887e1a7070ca526/2-12-sec-static-files.patch?part=0.0.1&view=1&vt=ANaJVrGrEs8fNpWjOUFuf3p1rWA83Dw-kPMJ8qeYExCi_n6nnuHcw53a2rWDfBwsfeA06s9Okm3LkpBK1W_b0vsqlsNAHGW1g0Z0T8WcmWxvqJCshdVpLts

Was manually applied to the backport branch.

This commit can be reverted as soon as sprockets 2.12.X is used.
Update ruby version to current stable 2.1.4

This release includes security fixes for the following vulnerabilities:

* CVE-2014-8080: Denial of Service XML Expansion
* Changed default settings of ext/openssl related to CVE-2014-3566

And there are some bug-fixes.