Generate API docs from source code comments (#2491)

* Generate api docs from source code

* Add a bunch of doxygen comments

* more doxygen comments

* Add the in-progress api docs

* script to generate docs from travis

* Add doc generation to the travis job

* make travis_docs.sh commit the work it does

* make sure the docs script exits cleanly

1 files changed, 61 insertions, 0 deletions

diff --git a/docs/api_sysex_tools.md b/docs/api_sysex_tools.md
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+# group `sysex_tools` {#group__sysex__tools}
+
+## Summary
+
+ Members                        | Descriptions                                
+--------------------------------|---------------------------------------------
+`public uint16_t `[`sysex_encoded_length`](#group__sysex__tools_1ga061e5607030412d6e62e2390d8013f0a)`(uint16_t decoded_length)`            | Compute the length of a message after it is encoded.
+`public uint16_t `[`sysex_decoded_length`](#group__sysex__tools_1ga121fc227d3acc1c0ea08c9a5c26fa3b0)`(uint16_t encoded_length)`            | Compute the length of a message after it is decoded.
+`public uint16_t `[`sysex_encode`](#group__sysex__tools_1ga54d77f8d32f92a6f329daefa2b314742)`(uint8_t * encoded,const uint8_t * source,uint16_t length)`            | Encode data so that it can be transmitted safely in a sysex message.
+`public uint16_t `[`sysex_decode`](#group__sysex__tools_1gaaad1d9ba2d5eca709a0ab4ba40662229)`(uint8_t * decoded,const uint8_t * source,uint16_t length)`            | Decode encoded data.
+
+## Members
+
+#### `public uint16_t `[`sysex_encoded_length`](#group__sysex__tools_1ga061e5607030412d6e62e2390d8013f0a)`(uint16_t decoded_length)` {#group__sysex__tools_1ga061e5607030412d6e62e2390d8013f0a}
+
+Compute the length of a message after it is encoded.
+
+#### Parameters
+* `decoded_length` The length, in bytes, of the message to encode.
+
+#### Returns
+The length, in bytes, of the message after encodeing.
+
+#### `public uint16_t `[`sysex_decoded_length`](#group__sysex__tools_1ga121fc227d3acc1c0ea08c9a5c26fa3b0)`(uint16_t encoded_length)` {#group__sysex__tools_1ga121fc227d3acc1c0ea08c9a5c26fa3b0}
+
+Compute the length of a message after it is decoded.
+
+#### Parameters
+* `encoded_length` The length, in bytes, of the encoded message.
+
+#### Returns
+The length, in bytes, of the message after it is decoded.
+
+#### `public uint16_t `[`sysex_encode`](#group__sysex__tools_1ga54d77f8d32f92a6f329daefa2b314742)`(uint8_t * encoded,const uint8_t * source,uint16_t length)` {#group__sysex__tools_1ga54d77f8d32f92a6f329daefa2b314742}
+
+Encode data so that it can be transmitted safely in a sysex message.
+
+#### Parameters
+* `encoded` The output data buffer, must be at least sysex_encoded_length(length) bytes long. 
+
+* `source` The input buffer of data to be encoded. 
+
+* `length` The number of bytes from the input buffer to encode.
+
+#### Returns
+number of bytes encoded.
+
+#### `public uint16_t `[`sysex_decode`](#group__sysex__tools_1gaaad1d9ba2d5eca709a0ab4ba40662229)`(uint8_t * decoded,const uint8_t * source,uint16_t length)` {#group__sysex__tools_1gaaad1d9ba2d5eca709a0ab4ba40662229}
+
+Decode encoded data.
+
+#### Parameters
+* `decoded` The output data buffer, must be at least sysex_decoded_length(length) bytes long. 
+
+* `source` The input buffer of data to be decoded. 
+
+* `length` The number of bytes from the input buffer to decode.
+
+#### Returns
+number of bytes decoded.
+