support tmux 2.4

[docwhat]

TMUX has changed the way bind-keys works in version 2.4+ This change
supports both older and newer versions.

In addition, I added tmux-is-at-least bash function to help with this and future changes in the TMUX commands.

Closes #76

[docwhat]

@bruno- It looks like this repository needs some love.

I'm willing to do a one-time clean up and close issues, accept PRs (or reject as needs be), etc. to clear out the back log of work.

I can probably be called on occasionally to do this work, but I can't promise (hence the "one-time").

[moniquelive]

+1 please merge it

[overcache]

@bruno- Please merge the code~~

[oblitum]

I hope he's doing well.

[bruno-]

Hey guys,

sorry for being away for so long (and thanks for the pings for this on twitter etc).

@oblitum I'm fine, thanks, just very busy.

@docwhat thank you for the offer for the one-time cleanup (and also for submitting this PR). Any chance we could find someone who could take over for the longer term? I'd like to avoid this situation happening again next year (or whenever upstream tmux changes some command).

[docwhat]

@bruno-

I've replied to a bunch of tickets. I suspect that some of the issues can be reduced by improving the documentation and maybe adding a github issue template.

Assuming nothing better comes along, I'll be using tmux-yank for the foreseeable future and will find issues like this in the future and would be willing submit fixes for it.

So go ahead and make me a maintainer and I'll start cleaning things up.

[oblitum]

This change breaks tmux-yank for me. I've frozen on tmux 2.3 because of the current issues on 2.4. The change from copy-pipe to copy-pipe-and-cancel even for older tmux makes yanking do nothing, I can only select text but not yank it.

[bruno-]

@docwhat thank you for volunteering sir, I just invited you!

[docwhat]

@bruno- I still can't accept PRs, though, such #86 . 😢 It says:

Only those with write access to this repository can merge pull requests.

Based on this page I think I need "write" or "admin" permissions (not "owner" though, which is the highest level).

(I'm assuming you want me to accept PRs and handle/close issues, etc.)

[bruno-]

@docwhat oh, it seems I forgot to add you to the repo after inviting you.. you should have "admin" permissions now.