Bump devDeps, microbundle, use TS strict mode

Author: fpapado

.eslintrc

@@ -0,0 +1,5 @@
+{
+  "extends": [
+    "plugin:jsx-a11y/recommended"
+  ]
+}

.prettier

@@ -0,0 +1,6 @@
+{
+  "printWidth": 80,
+  "bracketSpacing": false,
+  "singleQuote": true,
+  "trailingComma": "es5"
+}

ROADMAP.md

@@ -1,17 +1,29 @@
 # Always
+
 - Docs improvements! See [`FEEDBACK.md`](./FEEDBACK.md) for specific points.
 - Loading patterns and auxiliary component examples
 
 # v1
-- [ ] Elicit feedback and use cases for the public API
+
+- [x] Upgrade devDeps
+- [x] Upgrade microbundle
+- [ ] Check --external all consequence
+- [ ] Upgrade react-intersection-observer
+- [ ] Split out renderXYZ components
+- [ ] Refactor props
+- [ ] Props getter
+- [x] Elicit feedback and use cases for the public API
 - [ ] Investigate container `<div>`
 - [ ] Solidify `<noscript>` fallback
+- [ ] experimentalDecoding
 
 # Investigate
+
 - [ ] Auto sizes (if not handled already by browser behaviour)
 - [ ] cancel loading on componentWillUnmount
 
 # Later
+
 - [ ] abort loading if image leaves viewport and it has not loaded sufficiently
   - Likely a large change to how we do things
   - Possibly with using fetch and cancelling it