sad: death of panicless *+ smth

Give in in favor of str and utf8 with perfect valid state and panic
bailout everywhere in std.

Define some more Boot Info Format tags.

Cargo.lock

@@ -2,6 +2,12 @@
 # It is not intended for manual editing.
 version = 4
 
+[[package]]
+name = "ascii"
+version = "1.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d92bec98840b8f03a5ff5413de5293bfcd8bf96467cf5452609f939ec6f5de16"
+
 [[package]]
 name = "bios"
 version = "0.1.0"
@@ -10,5 +16,6 @@ version = "0.1.0"
 name = "oxide"
 version = "0.1.0"
 dependencies = [
+ "ascii",
  "bios",
 ]