Revert "Always trim newlines from commands, even continuations"

Removing newlines broke character counts on literals, leading to APPEND
statements and the like hanging.

This reverts commit 38943296dcd37cdab343bb8c377bf994b3bed68d.
Trim newlines before decoding base64 date

3894329 was overzealous, and removed newlines from all continuations,
including inline literals; however, the need to ensure newlines are
removed before decoding base64 data is still present.  Explicitly strip
newlines before decoding base64'd AUTHENTICATE data.
Version 1.36 releng