Add NOTE: for 'Optimize Network Kernel Parameters' section
Copy input-plugin-overview.txt ja/input-plugin-overview.txt
Translate ja/input-plugin-overview.txt in Japanese
Merge pull request #53 from fluent/add-note-for-tw-parameters

Add NOTE: for 'Optimize Network Kernel Parameters' section
Add "Nintendo Inc." to users.
Add NOTE: for 'Optimize Network Kernel Parameters' section to Japanese version.
Merge pull request #55 from suzukaze/ja-input-plugin

Translate ja/input-plugin-overview.txt in Japanese
Add `max_retry_wait` to out_forward.txt
Merge pull request #56 from sonots/patch-2

Add `max_retry_wait` to out_forward.txt
Copy in_forward.txt ja/inforward.txt
Translate ja/in_forward.txt in Japanese
remove unneeded "
replace element->part

To uniform word like other plugins of `tag_parts` placeholder.

* https://github.com/tagomoris/fluent-plugin-forest
* https://github.com/sonots/fluent-plugin-record-reformer
* https://github.com/fluent/fluent-plugin-rewrite-tag-filter
add doc, rewrite_tag_filter
Merge pull request #58 from y-ken/change-word-elements-to-parts

Replace element->part at the page of Match Pattern
add ltsv and nginx descriptions
Replace Fluent-cat with fluent-cat in ja/in_forward.txt
Replace Fluent-cat with fluent-cat in in_forward.txt
Merge pull request #61 from suzukaze/in_forward-plugin

Replace Fluent-cat with fluent-cat in in_forward.txt
Merge pull request #57 from suzukaze/ja-in_forward-plugin

Translate ja/in_forward.txt in Japanese