Merge #138

138: Fix some clippy lints r=matklad a=alanhdu

I went ahead and fixed all the clippy lints (there were a couple I thought would be better unfixed and added `cfg` statements to allow them) and also re-enabled clippy and rustfmt in CI.

They were disabled with `no time to explain, disable clippy checks`, so hopefully this won't go against whatever the reason at the time was 😆.

One question about the CI though: right now, it's an allowed failure that runs against the latest nightly each time. Would it be better to pin it to a specific nightly (or use the `beta` versions) to lower the churn?

Co-authored-by: Alan Du <alanhdu@gmail.com>

crates/ra_analysis/src/imp.rs

@@ -426,12 +426,12 @@ impl AnalysisImpl {
                                     .text()
                                     .slice(range_search)
                                     .to_string()
-                                    .matches(",")
+                                    .matches(',')
                                     .count();
 
                                 // If we have a method call eat the first param since it's just self.
                                 if has_self {
-                                    commas = commas + 1;
+                                    commas += 1;
                                 }
 
                                 current_parameter = Some(commas);