Add more documentation

docs/Shearwater.md

@@ -1,13 +1,15 @@
 # Shearwater Bluetooth Import
 [Shearwater](https://www.shearwater.com/) Petrel and Perdix computers use the "Petrel Native Format" for bluetooth
-communication. This format is not public, so this is based on code in [libdivecomputer](https://github.com/libdivecomputer/libdivecomputer/blob/master/src/shearwater_petrel.c).
+communication. This format is not public, so this is based on code in
+[libdivecomputer](https://github.com/libdivecomputer/libdivecomputer/blob/master/src/shearwater_petrel.c).
 
 
 ## Bluetooth LE
-Shearwater devices use a single serialPort characteristic (UUID: `27b7570b-359e-45a3-91bb-cf7e70049bd2`) for receiving (NOTIFY) and sending (WRITE) messages. 
+Shearwater devices use a single serial port characteristic (UUID: `27b7570b-359e-45a3-91bb-cf7e70049bd2`) for receiving
+(NOTIFY) and sending (WRITE) messages.
 
 ## Download
-We can send commands over the serialPort characteristic to download **raw chunks of memory**:
+We can send commands over the serial port characteristic to download **raw chunks of memory**:
 - `0x34`: Start download with given memory address and size.
 - `0x35`: Enabled or disable compression
 - `0x36`: Fetch the next block of current download
@@ -16,3 +18,6 @@ We can send commands over the serialPort characteristic to download **raw chunks
 There are two locations of interest:
 - `0xE0000000`: Manifest pages
 - `0x80000000`: Dive data
+
+See [ShearwaterConnection.kt](../data/src/main/kotlin/cloud/mike/divelog/data/importer/shearwater/ShearwaterConnection.kt)
+for implementation details.