New debug channel dc::snapshot.
Add option for Horizontal buttons on Contacts floater.

Adds Use horizontal buttons for contacts floater (needs restart) to Vanity Preferences.
Adds ContactsUseHorizontalButtons.
Adds FloaterContactsHorizRect for saving horizontal contacts rect.
Adds panel_friends_horiz.xml, panel_group_horiz.xml, and floater_my_friends_horiz.xml

Also corrects string value for FloaterContactsRect
Split off certain preferences into new Adv. Chat subtab Chat UI

From Text Chat: Disallow communicate shortcut opening detached friends list
From Vanity: Use horizontal buttons for contacts floater (needs restart)
The rest were in Chat/IM of Vanity.
Optionally, have IM buttons on the same line as the person's name.

Adds UseConciseIMButtons.
Adds floater_instant_message_concisebuttons.xml
Adds Have buttons on the same line as name for IMs (Affects new IMs) checkbox to Adv. Chat's Chat UI tab.
Applied STORM-1209 and added string AGroupMemberNamed for translation.
Vertical space recovered
Fixed LLUploadDialog to display it's text.

Also made the view rectangle have some minimal size (1/10th of the
screens width and height).
Increased the used font a bit.
Fixed removal of the dialog in the case of uploading to profile feed.
Upload larger original to profile feed.
Fine tune of private (libcwd) assertion.

It turns out that it's possible to receive data before an upload
finished when the server sends HTTP_BAD_REQUEST in the middle of the
upload (this happens to me when I try to upload a 6000x6000 image to my
profile feed, with is a 44MB file). So, in that case the finished upload
detection did not fail and we shouldn't assert.
Add getName() to every non-base class Responder object.
Unhide Client column properly on non-SL Grids.
Use multiple cores for compilation of the Debug build
Compile fix for VC++
Fix Issue 590: Debug Settings parameters setting is seriously bugged
Warn more clearly about LLRadioGroup::setValue being used wrong, and attempt to recover with LLUICtrl::setValue.
Fix group buttons in horizontal and allow the horizontal buttoned friends and groups floater to take up minimal space.
Fill fd_sets AFTER processing command queue.
Fix the "map/set iterators incompatible" bug.

cookies is only valid when AIHTTPReceivedHeaders::getValues return true.
Fix upload snapshot to inventory callback mechanism.
Do not freeze UI when snapshot floater is opened the first time.