autocompletion bugs

[soonhokong]

@leodemoura reported the followings:

• The input method only worked for “\fun” and “\eq”. Everything else I tried did not work: “\Pi”, “\r”, “\tr”, “\sy”, “\x”, “\forall”. My conjecture is: if auto-completion is activated, then the input method does not work. For example, when I type “\f” the auto-completion is already suggesting “forall”, and it seems to block the input method.
• The auto-completion gets “confused” with hierarchical names. If I type “eq.sy”, it will show “eq.symm” as a possible candidate. However, if I select it, the text becomes “eq.eq.symm” instead of “eq.symm”.

[soonhokong]

The first item was fixed when I was at MSR. The second item is fixed by https://github.com/leanprover/leanprover.github.io/commit/219662bb6831b9385f21e7be85987dac5529b955 and https://github.com/leanprover/ace/commit/663876f674e497ba2f0a8b64346e3da60dadf49f.

eq.sy  => ctrl + space / choose 'eq.symm' => eq.symm
sub_lt => ctrl + space / choose 'int.sub_lt_right' => int_sub_lt_right