add /undo, update help, readme and changelog; fix follow to join

Cargo.lock

@@ -276,7 +276,6 @@ checksum = "ea57b42383d091c85abcc2706240b94ab2a8fa1fc81c10ff23c4de06e2a90b5e"
 [[package]]
 name = "elefren"
 version = "0.22.0"
-source = "git+https://git.ondrovo.com/MightyPork/elefren-fork.git?rev=a0ebb46#a0ebb46542ede2d235ca6094135a6d6d01d0ecb8"
 dependencies = [
  "chrono",
  "doc-comment",
@@ -328,7 +327,7 @@ checksum = "e88a8acf291dafb59c2d96e8f59828f3838bb1a70398823ade51a84de6a6deed"
 
 [[package]]
 name = "fedigroups"
-version = "0.2.4"
+version = "0.2.5"
 dependencies = [
  "anyhow",
  "clap",