Add ac-sage-string-trim-left.
Add ac-sage-repl-doc.
Add ac-source-repl-sage-commands.
Refactoring.
cache the result of ac-sage-doc.
Use sage-shell:trim-left.
Add ac-sage--doc-clear-cache.
Add ac-sage--sage-commands-doc-cached.
Renaming and removed unused variable.
Fixed ac-sage--cache-doc.
Renaming and modify ac-sage-commands-candidates.
Modified ac-sage--doc.
Fixed ac-sage-commands-candidates.