[ci skip] Revert some cosmetic changes from PR #2524, for consistency
[ci skip] Adding another cyrillic character to config/foreign_chars.php (#2509)
Merge pull request #2502 from enapupe/patch-1

Update Profiler.php to show HTTP_DNT status
Add changelog entry for PR #2502
Merge pull request #2417 from thefuzzy0ne/fix/upload_dry

Fix/upload dry
Merge pull request #2411 from Dumk0/patch-1

fix typos in Parser.php
Merge pull request #2452 from thallisphp/patch-3

Removed unused variable $name in Cache_memcached.php
Merge pull request #2370 from TheDragonSlayer/patch-1

Update user_agents.php (Added PS Vita)
[ci skip] Just removing some empty lines
Cherry-picking some changes from PR #2425:

- Session events logging (debug)
- Bug fix for OCI8 method stored_procedure()
Merge pull request #2447 from rlerdorf/develop

A few minor fixes and cleanups
[ci skip] Remove some empty lines
Fix #2490 (an improved version of PR #2534)
Add an optional  parameter to URL helpers base_url() and site_url() (supersedes #2535)
Add that parameter for real :)
Micro-optimization on base_url() & site_url()
Add color customization to the CAPTCHA helper

Ref: Issue #867 & PRs #1405, #2485
[ci skip] Remove a description for a non-existing shadow color in the CAPTCHA helper docs
Fix a Memcache(d) default configuration bug (based on #249)
More verbose error messages for incorrect/missing database groups (based on PR #2040)