Diagnosis and warning about invalid rules

Adguard 1.8.10
Safari 13.1.2 (13609.3.5.1.5)
MacOS 10.13.6 (17G14042)

### Problem Description

Bug #455 and bug #485 ("won't do" and "won't do") are both due to change in adguard parsing behaviour to change to silently reject "invalid" rules.

As a user, this is not a satisfactory resolution, as there appears to be no way to determine if a rule is synatically valid, aside from happening to notice that a rules does not appear to work after an adguard update (or after making a mistake editing a rule).

The user then has to performing tiresome trial and error on the user rules configuration file, first to find the offending rule, and second level of trial-and-error to attempt to guess the Adguard parser's precise criteria.

It's even harder to work out the problem when something that worked, perhaps accidentally, for years in adblock ublock etc suddenly stops working, because the rule "looks good" and nothing was edited.

"The rule is invalid, you shouldn't use pipe characters in the cosmetic rules." was news to me.

Note that I do have "Verbose logging" enabled.
I can still find nowhere where Adguard mentions that it is silently ignoring a rule that it determined to be syntatically invalid.

### Proposed Solution

Log information about invalid rules in some location that the user can find it, and notify user when rules have been ignored.