ST / Mbed OS mbed-os-example-client-IKS01Ax

mbedOS client example, modified to push X-Nucleo-IKS01A1/2 Environmental Sensor data to mbed Cloud Connector.

Dependencies:   X_NUCLEO_IKS01A1 X_NUCLEO_IKS01A2

The application is derived from the official mbedOS client example (link) and has been tested using a X-NUCLEO-IKS01A2 (default) or a X-NUCLEO-IKS01A1 motion and environmental sensors expansion board connected to a ST NUCLEO-F429ZI platform.
The following steps should be performed to make the application work:

• Register and login into ARM mbed Connector.
• Replace the default and empty security.h file with the one associated with your account and provided by the Connector (Security Credentials menu).
• In order to use X-NUCLEO-IKS01A1 instead of default X-NUCLEO-IKS02A1 comment out the IKS01A2 macro definition in main.cpp file.
• Choose NUCLEO-F429ZI as a target either from online compiler or from CLI, compile and flash.
• Connect the board to your ethernet network, open a serial terminal (params 115200N1) and wait that the client is connected to the mbed Connector.
• Press user button to start acquiring and pushing the environmental (pressure, temperature and humidity) data.

Note: environmental data are expressed using IPSO representation based on OMA LWM2M standard.

Note: This is just a template, so feel free to use/remove the unnecessary things

Please note that if your issue is reproducible on a specific configuration only,
it's likely an mbed-OS issue rather than mbed-os-example-client issue. We recommend
reporting the the issue then directly to 
[mbed-os reposititory](https://github.com/ARMmbed/mbed-os/issues) - please also
try searching for duplicates before filing a new one.

### Description
- Type: Bug | Enhancement | Question
- Related Issue: `#abc`

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## Bug

**Version information**
(`mbed ls`)

**Environment details**
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Compiler & other relevant tools - version information.

**Expected Behavior**

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**Steps to Reproduce**

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## Enhancement

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## Question

**How to?**