New search filter features: "NOT" modifier. And "Contains(args)" filter.

There's currently a "from" filter, so I can do a [from:user#1234], and the results will consist of messages sent from said user. But what if I want to do the inverse?

[not: from:user#1234].

I suggest allowing users to prefix the search filters with a "not" modifier so we can ignore specific results. This will enable users to perform searches at a higher degree of complexity.

Now, on to the "Contains" filter, what if I barely remember a sentence someone said, and I really want to go back and find it? All I remember is it contains two specific words, but I don't even remember which order they were in. I don't know who said it, but I sure as hell know user#1234 didn't say it, despite him having posted many messages with the same two words.

I could perform a nice search like this:

[not: from:user#1234] [contains(word1, word2)]

"Contains" finding every message that is not from user#1234 that contains word1 AND word2 in any order.