Update Lossage chapter of Emacs manual.

Update Lossage chapter of Emacs manual.

* doc/emacs/trouble.texi (Lossage): Refer to Bugs node for problems.
(DEL Does Not Delete): Don't use "usual erasure key" teminology.
(Screen Garbled): Don't refer to terminal "manufacturers".
(Total Frustration): Node deleted.  Eliza is documented in
Amusements now.
(Known Problems): More info about using the bug tracker.  Mention
debbugs package.
(Bug Criteria): Copyedits.
(Understanding Bug Reporting): Mention emacs -Q.