FIX: force encoding for title field

Job exception: incompatible character encodings: UTF-8 and ASCII-8BIT
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This exception rise up for correct(!) UTF-8 cyrillic (in my case, but non-latin overall, I suppose) in title field during RSS polling (feed polling url) and breaks topics creation.
So, just force_encoding() makes it work.
due to travis error message: can't modify frozen string
FIX: incorrect edit notification in user stream
FIX: missing edit notifications when post edited by multiple users
FIX: dismissed banner topic returned after saving user profile
UX: improve select2 category picker styling
FIX: select + replies could not be selected
incorrect fix for avatar height in topic map
clean up /about page styles on mobile
use proper trash watermark
tweaks to make flagging page better on mobile
FIX: allow admins to search users by email
changes: topic title editor layout, badge alignment in scrolled header
Merge pull request #2856 from awesomerobot/master

changes: topic title editor layout, badge alignment in scrolled header
Added easy impersonate route while in development mode
Also import Q+A comments
security updates, firewall note
UX: Remove sortable column from "Topic" and "Users" column.
FIX: Clicking "Latest" while ordering by a column should reset the
order.
FEATURE: trust level 3: likes received must be on min_likes_received/3 different days, and be from min_likes_received/4 different users
Merge branch 'master' of github.com:discourse/discourse