tab-line-mode improvement

[Kiso Katsuyuki]

Hi all,

I came up with two improvements on tab-line-mode:

1. Suppress-errors...
   It suppresses errors when tab-line-switch-to-prev-tab or
   tab-line-switch-to-next-tab is invoked in the window which has no tabs.
2. Introduce-a-new-variable... (after #1 patch is applied)
   It introduces a new variable tab-line-switch-cycling which enables cycling tab switch.

These patches are attached.

I sent patches for the first time, any advices, comments, or questions are very welcome.

Best regards,

Katsuyuki

0001-Suppress-errors-of-tab-line-switch-functions.patch
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0001-Introduce-a-new-variable-tab-line-switch-cycling.patch
Description: Text Data