patch 8.2.0155: warnings from MinGW compiler; tests fail without +float

Problem:    Warnings from MinGW compiler. (John Marriott) Json test fails when
            building without +float feature.
Solution:   Init variables. Fix Json parsing. Skip a few tests that require
            the +float feature.

src/version.c

@@ -742,6 +742,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    155,
 /**/
     154,
 /**/