build: use explicit braces around else statement

Warning detected by clang.

Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk>
d4d_icon: remove redundant declaration

D4D_IconGetBmpCount is already declared in d4d_icon.h

Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk>
d4d_scheme: scrExitBtnBckg missing field initialiser

Detected by clang.

Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk>
d4d_screen: initialise all members of struct D4D_STRING_S

Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk>
d4d_low: add driver FillRect function

Some TFT drivers have acceleration, eg. S1D13506.
Use Hardware features if available.

Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk>
d4d_button: add colour invert on keypress

This adds a new button style D4D_BTN_F_INVERT.
If set the button foreground/background will swap dependong on whether
pressed ot released.

Signed-off-by: Spencer Oliver <spen@spen-soft.co.uk>
Merge branch 'pending' of https://github.com/ntfreak/eGUI into ntfreak-pending
Just cosmetically change of branches
Accept all commit(changes) of ntfreak, except the extend of lld API, that MUST be better defined to support not only rectangle, but all possible acceleration features.
Merge branch 'ntfreak-pending'
Just updated the project files to reflect missing test source files.