Add README for span-suggester project (#14)

The spancat blogpost links it here, it may be nice to add some README
so that it's more presentable.

Author: ljvmiranda921

projects/span_suggesters/README.md

@@ -0,0 +1,46 @@
+<!-- SPACY PROJECT: AUTO-GENERATED DOCS START (do not remove) -->
+
+# 🪐 spaCy Project: Span Suggesters
+
+This project introduces new experimental suggester functions
+
+## 📋 project.yml
+
+The [`project.yml`](project.yml) defines the data assets required by the
+project, as well as the available commands and workflows. For details, see the
+[spaCy projects documentation](https://spacy.io/usage/projects).
+
+### ⏯ Commands
+
+The following commands are defined by the project. They
+can be executed using [`spacy project run [name]`](https://spacy.io/api/cli#project-run).
+Commands are only re-run if their inputs have changed.
+
+| Command | Description |
+| --- | --- |
+| `install` | Install requirements |
+| `data` | Format Healthsea annotations into .spaCy training format |
+| `train_spancat` | Train a spancat model |
+
+### ⏭ Workflows
+
+The following workflows are defined by the project. They
+can be executed using [`spacy project run [name]`](https://spacy.io/api/cli#project-run)
+and will run the specified commands in order. Commands are only re-run if their
+inputs have changed.
+
+| Workflow | Steps |
+| --- | --- |
+| `all` | `data` &rarr; `train_spancat` |
+
+### 🗂 Assets
+
+The following assets are defined by the project. They can
+be fetched by running [`spacy project assets`](https://spacy.io/api/cli#project-assets)
+in the project directory.
+
+| File | Source | Description |
+| --- | --- | --- |
+| `assets/healthsea_ner.jsonl` | URL | Annotations from the Healthsea dataset |
+
+<!-- SPACY PROJECT: AUTO-GENERATED DOCS END (do not remove) -->