Indentation fixes

- Fix dir-locals so emacs won't inject occasional tabs to case statements.
- Fix stray tab indentation in example programs. (Thx @pfalcon for pointing this out)

.dir-locals.el

@@ -1,5 +1,9 @@
-((c-mode
-  (c-file-style . "BSD")
+(
+ (nil
+  (indent-tabs-mode . nil)
+  )
+ (c-mode
+  (c-file-style . "bsd")
   (c-basic-offset . 4)
   )
  )

README.md

@@ -96,6 +96,12 @@ For code submissions based on reverse engineered binary functionality, please ei
 
 The best way to write suitable code is to first add documentation somewhere like the [esp8266 wiki](https://github.com/esp8266/esp8266-wiki/) describing factual information gained from reverse engineering - such as register addresses, bit masks, orders of register writes, etc. Then write new functions referring to that documentation as reference material.
 
+## Coding Style
+
+For new contributions, please use BSD style and indent using 4 spaces. If you're an emacs user then there is a .dir-locals.el file in the root which configures cc-mode.
+
+Upstream code is left with the indentation and style of the upstream project.
+
 ## Sponsors
 
-Work on esp-open-rtos is sponsored by [SuperHouse Automation](http://superhouse.tv/).
+Work on esp-open-rtos has been sponsored by [SuperHouse Automation](http://superhouse.tv/).

core/esp_gpio_interrupts.c

@@ -15,22 +15,24 @@
      be enough in all cases.
 
    void gpio01_interrupt_handler(void) {
-
+       // Do something when GPIO 01 changes
    }
 
+   void gpio12_interrupt_handler(void) {
+       // Do something when GPIO 12 changes
+   }
+
+   OR
+
    - Implement a single function named gpio_interrupt_handler(). This
      will need to manually check GPIO_STATUS_REG and clear any status
      bits after handling interrupts. This gives you full control, but
      you can't combine it with the first approach.
 
-     void gpio_interrupt_handler(void) {
 
-     }
-
-
- * Part of esp-open-rtos
- * Copyright (C) 2015 Superhouse Automation Pty Ltd
- * BSD Licensed as described in the file LICENSE
+  Part of esp-open-rtos
+  Copyright (C) 2015 Superhouse Automation Pty Ltd
+  BSD Licensed as described in the file LICENSE
  */
 #include "esp8266.h"
 

core/include/esp/iomux_private.h

@@ -44,4 +44,3 @@ INLINED uint8_t iomux_to_gpio(const uint8_t iomux_number)
 }
 
 #endif
-

examples/http_get_ssl/main.c

@@ -222,4 +222,3 @@ static void display_cipher(SSL *ssl)
 
     printf("\n");
 }
-

examples/simple/main.c

@@ -42,5 +42,3 @@ void user_init(void)
     xTaskCreate(task1, (signed char *)"tsk1", 256, &mainqueue, 2, NULL);
     xTaskCreate(task2, (signed char *)"tsk2", 256, &mainqueue, 2, NULL);
 }
-
-