ENH: clean up some help text

Source/cmIfCommand.h

@@ -194,15 +194,15 @@ public:
       "\n"
 
       "The if statement was written fairly early in CMake's history "
-      "and it has some convenience features that may be confusing for "
-      "new users. The if statement reduces operations until there is "
+      "and it has some convenience features that are worth covering. "
+      "The if statement reduces operations until there is "
       "a single remaining value, at that point if the case "
       "insensitive value is: ON, 1, YES, TRUE, Y it returns true, if "
       "it is OFF, 0, NO, FALSE, N, NOTFOUND, *-NOTFOUND, IGNORE it "
       "will return false. \n"
 
-      "This is fairly reasonable. The convenience feature that makes "
-      "it more confusing is how CMake handles values that do not "
+      "This is fairly reasonable. The convenience feature that sometimes "
+      "throws new authors is how CMake handles values that do not "
       "match the true or false list. Those values are treated as "
       "variables and are dereferenced even though they do not have "
       "the required ${} syntax. This means that if you write\n"

Source/cmPolicies.cxx

@@ -360,10 +360,10 @@ cmPolicies::cmPolicies()
     CMP0012, "CMP0012",
     "In CMake versions prior to 2.6.5 the only boolean constants were 0 and 1. "
     "Other boolean constants such as true, false, yes, no, "
-    "on, off, y, n, notfound, ignore were recognized in some cases but not all. "
-    "In later versions of cmake these values are treated as boolean constants "
-    "more consistently and should not be used as variable names. "
-    "Please do not use them as variable names.",
+    "on, off, y, n, notfound, ignore (all case insensitive) were recognized "
+    "in some cases but not all. In later versions of cmake these values are "
+    "treated as boolean constants more consistently and should not be used "
+    "as variable names. Please do not use them as variable names.",
     "The OLD behavior for this policy is to allow variables to have names such as "
     "true and to dereference them. "
     "The NEW behavior for this policy is to treat strings like true as a boolean constant.",