refactor(library): mark absurd_elim argument as implicit

Signed-off-by: Leonardo de Moura <leonardo@microsoft.com>
fix(emacs/lean-info): type of a symbol at the end of buffer
fix(emacs/lean-info): handle when both identifier and symbol info exist

Example: library/data/int/basic.lean file (398, 22)

The '+' symbol is attached with both of identifier info and symbol info

-- SYMBOL|398|22
+
-- ACK
-- IDENTIFIER|398|22
int.add
-- ACK
fix(emacs/lean-type): problem with lean-eldoc-nay-retry-time

If (current-idle-time) is non-zero, we need to set a timer to run
eldoc-documentation-function again when idle-time = (current-idle-time)
+ retry-delay.