add icons for checked+disabled checkbox and radio

core/img/actions/checkbox-checked-disabled.svg

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns="http://www.w3.org/2000/svg" height="16px" width="16px" version="1.1" xmlns:cc="http://creativecommons.org/ns#" xmlns:dc="http://purl.org/dc/elements/1.1/">
+ <path d="m2.5 2.5h11v11h-11z" fill="#fff"/>
+ <path d="m3 2c-0.554 0-1 0.446-1 1v10c0 0.554 0.446 1 1 1h10c0.554 0 1-0.446 1-1v-10c0-0.554-0.446-1-1-1h-10zm8.924 2.0664l1.433 1.4316-6.3648 6.365-4.2422-4.2439 1.4141-1.414 2.8281 2.8301 4.9318-4.9688z" fill="#969696"/>
+</svg>

core/img/actions/radio-checked-disabled.svg

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="UTF-8" standalone="no"?>
+<svg xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns="http://www.w3.org/2000/svg" height="16px" width="16px" version="1.1" xmlns:cc="http://creativecommons.org/ns#" xmlns:dc="http://purl.org/dc/elements/1.1/">
+ <path d="m8 1.5c-3.5899 0-6.5 2.9101-6.5 6.5s2.9101 6.5 6.5 6.5 6.5-2.9101 6.5-6.5-2.91-6.5-6.5-6.5z" fill="#fff"/>
+ <path d="m8 1a7 7 0 0 0 -7 7 7 7 0 0 0 7 7 7 7 0 0 0 7 -7 7 7 0 0 0 -7 -7zm0 1a6 6 0 0 1 6 6 6 6 0 0 1 -6 6 6 6 0 0 1 -6 -6 6 6 0 0 1 6 -6zm0 2c-2.2091 0-4 1.7909-4 4 0 2.209 1.7909 4 4 4 2.209 0 4-1.791 4-4 0-2.2091-1.791-4-4-4z" fill="#969696"/>
+</svg>