Add default tensor size guidance for text

[bhack]

No description provided.

[nfelt]

@bhack could you explain the motivation for this change? I believe by default the text plugin will use the TENSORS entry from DEFAULT_SIZE_GUIDANCE which is also 10, so this change would seem to be a no-op.

Also, I think to get the tests to pass you would need to add a dependency on the text_plugin to the application build target here:
https://github.com/bhack/tensorboard/blob/7ab07620a83c640c1b482fa2e3a6f8a4775e892e/tensorboard/backend/BUILD#L57-L73

[bhack]

Cause you cannot control the sampling from the interface i have some text data correlated to the images. So as the image has its own entry when I change it I want to change text with the same value without change the default for all.

[nfelt]

@bhack as of TensorBoard 1.9.0 there's a --samples_per_plugin flag you can use to override the default sample counts - can you just use that? See #1138 for details.

[bhack]

Ok it is the same. Is it the plural of the plugin name "s" suffix?

[nfelt]

The string to use is the same as the key of the DEFAULT_TENSOR_SIZE_GUIDANCE dictionary, the PLUGIN_NAME field from the respective plugin metadata. For the text plugin it's text and for the images plugin it's images.

[bhack]

ok thanks