Implement Actions, create a theme switcher action window

java/res/drawable/arrow_left.xml

java/res/drawable/eye.xml

java/src/org/futo/inputmethod/keyboard/KeyboardSwitcher.java

java/src/org/futo/inputmethod/keyboard/KeyboardView.java

java/src/org/futo/inputmethod/keyboard/MainKeyboardView.java

...o/inputmethod/keyboard/internal/KeyPreviewDrawParams.java

...to/inputmethod/keyboard/internal/KeyVisualAttributes.java

...g/futo/inputmethod/keyboard/internal/KeyboardBuilder.java

.../futo/inputmethod/keyboard/internal/KeyboardIconsSet.java

java/src/org/futo/inputmethod/latin/LatinIME.kt

java/src/org/futo/inputmethod/latin/LatinIMELegacy.java

java/src/org/futo/inputmethod/latin/uix/Action.kt

java/src/org/futo/inputmethod/latin/uix/ActionBar.kt

java/src/org/futo/inputmethod/latin/uix/BaseActions.kt

java/src/org/futo/inputmethod/latin/uix/theme/Theme.kt