Add copy about static, component image generator & large PRs (#53)

Author: kbx81

docs/contributing/code.md

@@ -59,6 +59,8 @@ In general, we try to avoid use of external libraries.
 - Components **must** use the provided abstractions like `sensor`, `switch`, etc. and should inherit from either
   `Component` or `PollingComponent`.
 - Components should **not** directly access other components -- for example, to publish to MQTT topics.
+- Use of `static` variables within component/platform classes is not permitted, as this is likely to cause problems
+  when multiple instances of the component/platform are created.
 - Components are required to dump their configuration using `ESP_LOGCONFIG` in the `dump_config()` method. This method
   is used **exclusively** to **print values** determined during `setup()` -- nothing more.
 - For time tracking, use `App.get_loop_component_start_time()` rather than `millis()`. Hardware time reads are slow

docs/contributing/docs.md

@@ -20,6 +20,14 @@ If you're not familiar with rST, see [rST syntax](#rst-syntax) for a quick prime
     - Dependent components (Instead, include a sentence explaining the dependency and a link to the dependency's
       documentation)
 - Pin numbers used in examples should be the string `GPIOXX` -- not a specific pin number.
+- When adding (a) new component(s)/platform(s), be sure to update the [main index page](https://esphome.io/components/)
+  appropriately:
+    - Insert your new component/platform _alphabetically_ into the relevant list(s) -- do **not** just append to the
+      end of any given component/platform list.
+    - If you need an image for your new component/platform, use our
+      [component image generator](https://github.com/esphome/component-image-generator). You can run this in a
+      container locally to generate the image or summon our bot to do so by adding a comment to your PR in the
+      `esphome-docs` repository: `@esphomebot generate image MyNewComponent`
 - If a component/platform is used exclusively/primarily on a single specific board (perhaps with dedicated pin
   numbers), a complete configuration for the component/platform on that specific board may be included as an example
   _at the end of the document._ This example must be clearly identified as being for that specific hardware and it may

docs/contributing/submitting-your-work.md

@@ -85,14 +85,30 @@ here are some tips:
   time commenting on/correcting your PR because you didn't name variables correctly or didn't prefix member variable
   accesses with `this->`, it wastes time we could be using to review other PRs which *do* follow the standards.
 - If you wish to take on a big project, such as refactoring a substantial section of the codebase or integrating
-  another open source project with ESPHome, please discuss this with us on [Discord](https://discord.gg/KhAMKrd) or
+  another open source project with ESPHome, please discuss this with us on [Discord](https://esphome.io/chat) or
   [create a discussion on GitHub](https://github.com/esphome/esphome/discussions) **before** you do all the work and
   attempt to submit a massive PR.
 - If you are not sure about how you should proceed with some changes, **please**
-  [discuss it with us on Discord](https://discord.gg/KhAMKrd) **before** you go do a bunch of work that we can't (for
+  [discuss it with us on Discord](https://esphome.io/chat) **before** you go do a bunch of work that we can't (for
   whatever reason) accept...and then you have to go back and re-do it all to get your PR merged. It's easier to make
   corrections early-on -- and we want to help you!
 
+#### How to approach large submissions
+
+If you have a (very) large amount of code (thousands of lines) you want to submit:
+
+- [Discuss it with us on Discord](https://esphome.io/chat) **before** you begin the work.
+- **Carefully plan a way to break the work into a series of smaller changes** which can be submitted independently of
+  each other. For example, consider a piece of sensor hardware which provides measurements of seven different
+  environmental parameters and can be connected via either I2C or SPI; the work might be broken into separate PRs for:
+    - Implementing the base "hub" component
+    - Extending the base for both I2C and SPI connectivity
+    - Adding the various sensor platforms to make available the data the sensor reports
+- It's reasonable to submit all the PRs at once, but, if you do so, be sure to:
+    - Link them together in the PR descriptions so that reviewers can follow the work.
+    - Indicate the order in which the PRs should be reviewed and/or merged, if relevant.
+    - Minimize (the potential for) conflicts as much as reasonably possible.
+
 ## Can I Help Review PRs?
 
 **YES! PLEASE!!!**