Add vim-airline back

[sheharyarn]

After updating my plugins today, airline stopped working. Noted a similar report in #26 and traced the change back to #21 (in edfed09). In the PR, you mentioned:

the current version is broken and I'm not using vim-airline at the moment

I don't agree. The material airline theme works great and I've had no issues so far (even if it might not look exactly like lightline's). I think it's better to wait for a PR from people who want it updated to resolve the issue instead of removing it outright and breaking vim configs for those who're happy with it.

Let me know what you think. Also, love the theme and thank you for porting it to vim!

[kaicataldo]

@sheharyarn Hey, thanks for the kind words! I'll see if I can find some time to add it back - I'm doing a bit more open source these days, so that's a distinct possibility! Just to clarify, the vim-airline theme was broken with the rewrite (but still worked in versions before the rewrite).

[sheharyarn]

My bad, that does seem to be the case. It doesn't look quite right after adding it back. For now, I'll continue to use the old version:

Plug 'kaicataldo/material.vim', {'commit': '5aabe47'}

Thanks!

[kaicataldo]

I haven't been able to get to this yet. Do you want to leave this PR open? The old Airline theme won't work any more, so unless you want to update it, maybe it would be better to close it. If you'd like to open an issue to track this, that would help me a lot though!

[sheharyarn]

Sure thing, I opened #31 to track the feature. Thanks!

[kaicataldo]

Appreciate it!