Move pages under tldr, lint run.sh, update docs

tldr/flow

@@ -0,0 +1,25 @@
+---
+syntax: markdown
+tags: [tldr, common]
+source: https://github.com/tldr-pages/tldr.git
+---
+# flow
+
+> A static type checker for JavaScript.
+> More information: <https://flow.org>.
+
+- Run a flow check:
+
+`flow`
+
+- Check which files are being checked by flow:
+
+`flow ls`
+
+- Run a type coverage check on all files in a directory:
+
+`flow batch-coverage --show-all --strip-root {{path/to/directory}}`
+
+- Display line-by-line type coverage stats:
+
+`flow coverage --color {{path/to/file.jsx}}`