ItemWidthStack can be empty, to remove one allocation per window

Store common stacked settings contiguously in memory to reduce cache misses & unnecessary heap allocations

Added PushButtonRepeat() / PopButtonRepeat(). REMOVED third 'repeat_if_held' parameter of Button() !

Added configurable io.KeyRepeatDelay, io.KeyRepeatRate

Simplified some widget code, moving alignment to RenderTextClipped()

Reordering parameters of internal RenderTextClipped()

Button centering left to RenderTextClipped function.

Button() closes active popup (#126) unsure about that

Refactor Button() and SmallButton() into a shared function ButtonEx()

Spacing + untabify

EndGroup() carries on the text base offset from the last line of the group (sort of incorrect but better than nothing)

Examples: various usage comments.

Added TextDisabled(), TextDisabledV() helpers.

WIP Menus: Fixed remaining inconsistency with stacks of popups. Activating/closing a menu close the parent popup. Added test case. (#126)

Merge remote-tracking branch 'origin' into 2015-05-menus

WIP Menus: Added support for disabled sub-menu (#126)

Comments. Examples: added empty if (MenuItem()) {} statements in more places to better document the typical use cases (#126)

Comments

WIP Menus: Implement amazon's dropdown-like triangle test for navigating sub-menus (#126)

WIP Menus: Recursive menu demo (#126). Actually useful to test sub-menu positioning.

SelectableEx: use flags internally (similar to ButtonBehavior)

WIP Menus: Closing sub-menu when hovering something else in the same parent window (#126) ...

Immediate open/close is error-prone

Comments

WIP Menus: Layout in menu-bar tweaks to lay better when mixed widgets (#126)

WIP Menus: Layout in menu-bar more standard, allows mixing different widgets in menubar. (#126) ...

Still some minor spacing bugs.

Selectable: text baseline alignment for line that aren't of text height.

WIP Menus: Sub-menu overlapping amount not hardcoded (#126)

WIP Menus: Fixed style.WindowPadding == 0 leading to zero-sized initial clipping rectangle leading to self-collapsing childs (#126)

Combo: empty label doesn't add ItemInnerSpacing alignment, matching other widgets

WIP Menus: Sub-menus appears over the parent-menu scrollbar if there is one (unsure about that) (#126)