RELEASE_NOTES: update ARTIQ-6 section

RELEASE_NOTES.rst

@@ -8,13 +8,22 @@ ARTIQ-6
 
 Highlights:
 
+* New hardware support:
+  - Zynq SoC core devices, enabling kernels to run on 1 GHz CPU core with
+    a floating-point unit for faster computations. This currently requires an external
+    repository (https://git.m-labs.hk/m-labs/artiq-zynq) and only supports the ZC706.
+  - Mirny 4-channel wide-band PLL/VCO-based microwave frequency synthesiser
+  - Fastino 32-channel, 3MS/s per channel, 16-bit DAC EEM
+  - Kasli 2.0
+* Matrix math support on the core device.
+* Trigonometric functions and miscellaneous math library support on the core device.
 * Performance improvements:
    - #1432: SERDES TTL inputs can now detect edges on pulses that are shorter
      than the RTIO period
    - Improved performance for kernel RPC involving list and array.
-* Coredevice SI to mu conversions now always return valid codes, or raise a `ValueError`.
-* Zotino now exposes `voltage_to_mu()`
-* `ad9910`: The maximum amplitude scale factor is now `0x3fff` (was `0x3ffe`
+* Coredevice SI to mu conversions now always return valid codes, or raise a ``ValueError``.
+* Zotino now exposes   ``voltage_to_mu()``
+* ``ad9910``: The maximum amplitude scale factor is now ``0x3fff`` (was ``0x3ffe``
   before).
 * Dashboard:
    - Applets now restart if they are running and a ccb call changes their spec
@@ -25,11 +34,16 @@ Highlights:
 * Core device: ``panic_reset 1`` now correctly resets the kernel CPU as well if
   communication CPU panic occurs.
 * NumberValue accepts a ``type`` parameter specifying the output as ``int`` or ``float``
-* A parameter `--identifier-str` has been added to many targets to aid
+* A parameter ``--identifier-str`` has been added to many targets to aid
   with reproducible builds.
+* Python 3.7 support in Conda packages.
 
 Breaking changes:
 
+* ``artiq_netboot`` has been moved to its own repository at
+  https://git.m-labs.hk/m-labs/artiq-netboot
+* Core device watchdogs have been removed.
+
 
 ARTIQ-5
 -------