fixes #19863; move sha1, md5 to nimble packages for 2.0 (#21702)

* move sha1, md5 to nimble packages

* boot the compiler

* fixes tests

* build the documentation

* fixes docs

* lol, I forgot koch.nim

* add `nimHasChecksums` define

* clone checksums but maybe copying is better

* bump nimble hash

* use ChecksumsStableCommit

* fixes tests

* deprecate them

* fixes paths

* fixes koch

lib/std/sha1.nim

@@ -26,6 +26,9 @@ runnableExamples("-r:off"):
     b = parseSecureHash("10DFAEBF6BFDBC7939957068E2EFACEC4972933C")
   assert a == b, "files don't match"
 
+
+{.deprecated: "use command `nimble install checksums` and import `checksums/sha1` instead".}
+
 import strutils
 from endians import bigEndian32, bigEndian64
 
@@ -281,4 +284,4 @@ proc `==`*(a, b: SecureHash): bool =
 
 proc isValidSha1Hash*(s: string): bool =
   ## Checks if a string is a valid sha1 hash sum.
-  s.len == 40 and allCharsInSet(s, HexDigits)
+  s.len == 40 and allCharsInSet(s, HexDigits)