4a3c5c525b Merge remote-tracking branch 'origin/release_internal' into release_external
2b8d2e1356 Do not reset radio when MAC data request timeouts (#2647)
95c506a276 Frame counters for nw keys are now stored to NVM only after send key is set (#2641)
3b3010a79b Adjusted stagger random to [min,min+max] and for small nw set the stagger value to 10 seconds
02bc33a242 Adjusted security protocol (EAP-TLS,4WH,2WH) retry timers
eb26726020 High Priority timestamp compare overflow support fix.
928723a33e FHSS WS: Initialize broadcast channel count when enabling FHSS (#2642)
6040d703c8 Updated change log
667b191223 Changed initial EAPOL-key retries from trickle to exponential backup
d925145d33 Add RTT calculation for DHCP Time calculation
0b82953567 Traceroute bug fix.
04de6e26d8 Merge pull request #2638 from PelionIoT/mbed_os_fix_ufsi_calculation
20123477c6 Fixed FHSS UFSI calculation unit tests
436f16e84f Handle timer rollover in calculate_ufsi
411cf5c7a4 coding style
d6f44218d6 Correct ufsi timing calculation
560619d85d Add network time vendor data element to DHCPv6 reply message
6d290dc3c1 System time read/write callbacks (#2637)
7905df666d Restart or remove transmission when MAC data request timeouts (#2636)
c97695cfc6 Bug fix: EAPOL parent compare fix
e283e6285c Fixed channel mask usage with OFDM configurations (#2633)
24168f891b Do not send too old packets (#2632)
dbd83be16d Fix copyrights (#2631)
7f0cffdbf7 Merge pull request #2630 from PelionIoT/use_pelion_copyright
511bd5a3ad Corrected coding style
57ec0281a8 Corrected comparison
7d853de862 When EAPOL waiting queue is full oldest entry is removed
acf580fbd0 Update copyright in changed MDNS files
933c0bbf0a Update copyright
3aeb2af77c Statistics for data request latencies (#2629)
3f7eae64ef EAPOL FHSS temp entry discover
5200b666e7 DHCP time elapsed time write fix.
0536874f64 Removed empty EAPOL-key message send after 4WH completion to nodes on relay
8a2a683aef Fixed DHCP wrong time elapsed value write.
283f2ee685 DHCPv6 update:
99be7783ec EAPOL temp neighbour update
4f9e3d12ab Adaptation layer to remove oldest packet first
20f1f6492f Added ignoring of retry messages from RADIUS server when waiting EAP-TLS
8a8b407c47 Add RSL check for ETX Calculation for RPL parent selection
c05e1da757 Fix DHCP server Uninitialized memory read
77229eefa6 Fix CPP error from domain prefix check
7e47889111 support filtering of EAPOL parents based device-min-sens configuration
618a19192c Wi-SUN Expedite forward state update
4371462d66 Fix NULL read from RPL header addition
7802c7ee97 Update CHANGELOG.md
b2c810402c CHANGELOG for Nanostack v13.0.0 (#2615)

git-subtree-dir: connectivity/nanostack/sal-stack-nanostack
git-subtree-split: 4a3c5c5

```
connectivity
├── netsocket
├── lwipstack
├── nanostack
│   ├── mbed_lib.json // nanostack-interface's mbed_lib.json
│   ├── include
│   │   └── nanostack // headers from features/netsocket/nanostack-interface
│   ├── source        // sources from features/netsocket/nanostack-interface
│   ├── coap-service  // used by Thread only - deprecate?
│   ├── mbed-mesh-api
│   ├── nanostack-hal-mbed-cmsis-rtos // HAL porting layer for Nanostack on mbed with CMSIS-RTOS
│   ├── sal-stack-nanostack
│   └── sal-stack-nanostack-eventloop
├── cellular                // previously in features/cellular/framework/
├── ...

```

This PR is a part of a wider \connectivity refactoring and implements the above new directory structure for \nanostack.