Panel: Do not scroll to top upon updatelayout

Closes gh-7128
Fixes gh-6688
Re gh-5535
Docs: Updated contributing guidelines

Fixes gh-6983
Icons: External PNG CSS - Clean up a diff artifact

Introduced by commit bbb3bd5.

Closes gh-7112
Fixes gh-7182
Page and dialog: Update metadata

Fixes gh-7168
Build: Updated AUTHORS.txt
Textinput: Remove trailing comma from autogrow

Fixes gh-7171
Build: Add option "es3" to jshint

Closes gh-7173
Fixes gh-7172
Panel: only call getWrapper on create or when page changes for external

Fixes gh-6885
Fixes gh-6260
Closes gh-7004
Build: Tag demos.jquerymobile.com repo on release

Fixes gh-7191
Checkboxradio: Always uncheck the rest of the input set upon input click

Closes gh-7183
Fixes gh-7180
Flipswitch: Override rules for fieldcontainers inside popups

Fixes gh-7174
Slider: Override rules for fieldcontainers inside popups for flip switch
Theme: No shorthand to set background color only

Fixes gh-6839
Panel: Panel classes set on wrong page

Closes gh-6920
Fixes gh-6650
Updating the master version 1.4.3pre.
All: Fix demos markup inconsistencies discovered by cheerio

Closes gh-7212
Fixes gh-7211
Demos: highlight is now correctly removed on cancelation

In swipe to delete demo, the highlight is properly removed from the selected
list item on cancelation of the deletion.

Closes gh-6893
Fixes gh-6892
Demos: Pre-render collapsibles in demos left-side menu

Fixes gh-7225
Demos: fix style on listview-linkbar demo
Listview: linkbar demo scroll handler not working and updating to 1.4

Fixes gh-7129
Closes gh-7131