Tweak accent colour and drawables

The accent colour resource has been renamed to "accent" (was:
"accent_1") to reflect that it's the only accent colour.

A semi-transparent version of the same colour has been added alongside,
that is used for pre-4.0 list view item backgrounds in the schedule
sessions list.

Other accent drawables were also updated to match the current accent
colour.
PNG crunching

Re-crunch all the PNGs using ImageOptim (http://imageoptim.com/).
Saved 96.3KB out of 224KB. 43% overall.
Merge branch 'accentcolor' of git://github.com/rock3r/iosched into rock3r-accentcolor

Conflicts:
	android/src/main/res/drawable-hdpi/conference_ic_launcher.png
	android/src/main/res/drawable-hdpi/conference_ic_notification.png
	android/src/main/res/drawable-hdpi/ic_live_now_glyph.png
	android/src/main/res/drawable-hdpi/schedule_list_item_bg_normal.9.png
	android/src/main/res/drawable-hdpi/stream_list_divider.9.png
	android/src/main/res/drawable-hdpi/stream_list_item_bg_normal.9.png
	android/src/main/res/drawable-ldrtl-xhdpi/add_schedule_button_checked_default.9.png
	android/src/main/res/drawable-ldrtl-xhdpi/add_schedule_button_checked_focused.9.png
	android/src/main/res/drawable-ldrtl-xhdpi/add_schedule_button_checked_pressed.9.png
	android/src/main/res/drawable-ldrtl-xhdpi/add_schedule_button_unchecked_default.9.png
	android/src/main/res/drawable-ldrtl-xhdpi/add_schedule_button_unchecked_focused.9.png
	android/src/main/res/drawable-ldrtl-xhdpi/add_schedule_button_unchecked_pressed.9.png
	android/src/main/res/drawable-ldrtl-xhdpi/grey_border_inset_lr.9.png
	android/src/main/res/drawable-ldrtl-xhdpi/grey_frame.9.png
	android/src/main/res/drawable-ldrtl-xhdpi/grey_frame_on_white.9.png
	android/src/main/res/drawable-mdpi/conference_ic_launcher.png
	android/src/main/res/drawable-mdpi/grey_background_pattern_tile.png
	android/src/main/res/drawable-mdpi/ic_live_now_glyph.png
	android/src/main/res/drawable-mdpi/list_extra_button_left_border.9.png
	android/src/main/res/drawable-mdpi/schedule_list_item_bg_normal.9.png
	android/src/main/res/drawable-mdpi/stream_list_divider.9.png
	android/src/main/res/drawable-mdpi/stream_list_item_bg_normal.9.png
	android/src/main/res/drawable-nodpi/conference_widget_preview.png
	android/src/main/res/drawable-xhdpi/accent_bottom_border.9.png
	android/src/main/res/drawable-xhdpi/actionbar_inset_shadow.9.png
	android/src/main/res/drawable-xhdpi/actionbar_split_inset_shadow.9.png
	android/src/main/res/drawable-xhdpi/actionbar_stacked_background_pattern_tile.png
	android/src/main/res/drawable-xhdpi/add_schedule_button_checked_default.9.png
	android/src/main/res/drawable-xhdpi/add_schedule_button_checked_focused.9.png
	android/src/main/res/drawable-xhdpi/add_schedule_button_checked_pressed.9.png
	android/src/main/res/drawable-xhdpi/add_schedule_button_icon_unchecked.png
	android/src/main/res/drawable-xhdpi/add_schedule_button_unchecked_default.9.png
	android/src/main/res/drawable-xhdpi/add_schedule_button_unchecked_focused.9.png
	android/src/main/res/drawable-xhdpi/add_schedule_button_unchecked_pressed.9.png
	android/src/main/res/drawable-xhdpi/btn_radio_on_focused.png
	android/src/main/res/drawable-xhdpi/conference_actionbar_icon.png
	android/src/main/res/drawable-xhdpi/conference_actionbar_logo.png
	android/src/main/res/drawable-xhdpi/conference_ic_launcher.png
	android/src/main/res/drawable-xhdpi/conference_ic_notification.png
	android/src/main/res/drawable-xhdpi/dashclock_extension.png
	android/src/main/res/drawable-xhdpi/feedback_question_background.9.png
	android/src/main/res/drawable-xhdpi/grey_background_pattern_tile.png
	android/src/main/res/drawable-xhdpi/grey_border_inset_lr.9.png
	android/src/main/res/drawable-xhdpi/grey_frame.9.png
	android/src/main/res/drawable-xhdpi/grey_frame_on_white.9.png
	android/src/main/res/drawable-xhdpi/ic_verified_badge.png
	android/src/main/res/drawable-xhdpi/item_activated.9.png
	android/src/main/res/drawable-xhdpi/item_checked.9.png
	android/src/main/res/drawable-xhdpi/item_focused.9.png
	android/src/main/res/drawable-xhdpi/item_pressed.9.png
	android/src/main/res/drawable-xhdpi/list_extra_button_left_border.9.png
	android/src/main/res/drawable-xhdpi/schedule_button_more.png
	android/src/main/res/drawable-xhdpi/schedule_list_item_bg_normal.9.png
	android/src/main/res/drawable-xhdpi/stream_list_divider.9.png
	android/src/main/res/drawable-xhdpi/stream_list_item_bg_normal.9.png
	android/src/main/res/drawable-xhdpi/tab_color_ab_unselected.9.png
	android/src/main/res/drawable-xhdpi/tab_color_ab_unselected_focused.9.png
	android/src/main/res/drawable-xhdpi/tab_color_ab_unselected_pressed.9.png
	android/src/main/res/drawable-xhdpi/tab_color_selected.9.png
	android/src/main/res/drawable-xhdpi/tab_color_selected_focused.9.png
	android/src/main/res/drawable-xhdpi/tab_color_selected_pressed.9.png
	android/src/main/res/drawable-xhdpi/tab_color_unselected.9.png
	android/src/main/res/drawable-xhdpi/tab_color_unselected_focused.9.png
	android/src/main/res/drawable-xhdpi/tab_color_unselected_pressed.9.png
	android/src/main/res/drawable-xhdpi/textfield_activated.9.png
	android/src/main/res/drawable-xhdpi/textfield_default.9.png
	android/src/main/res/drawable-xhdpi/textfield_focused.9.png
	android/src/main/res/drawable-xhdpi/track_header_bottom_border.9.png
	android/src/main/res/drawable-xhdpi/transparent_background_pattern_tile.png
	android/src/main/res/drawable-xhdpi/transparent_background_pattern_tile_accent.png
	android/src/main/res/drawable-xxhdpi/conference_ic_launcher.png
	android/src/main/res/drawable-xxhdpi/conference_ic_notification.png
Merge branch 'rock3r-accentcolor' into ADD2014