fix issue with interupting timed functions; fix for parsing comsubs inside arith for commands; allow break and continue inside arith for expressions; fix for case-insensitive completion with multibyte chars; fix some minor memory leaks; reset read buffer if it returns partial results on EINTR; fix for undo in execute-named-command

tests/arith-for.tests

@@ -140,3 +140,7 @@ for ((j=;;)); do :; done
 echo X
 break
 echo Y
+
+# arithmetic for commands need to skip over command substitutions
+for (( $(case x in x) esac);; )); do break; done
+for (( ${ case x in x) esac; };; )); do break; done