efm32: return empty variable instead of Return('')
Delete trailing whitespace
Add mdk5 support in SCons tools
Add mdk5 project for stm32 bsps
Merge pull request #378 from grissiom/tools-next

efm32: return empty variable instead of Return('')
Merge pull request #381 from bright-pan/master

Add mdk5 building
Fix compile warning: variable "c" was declared but never referenced, when RT_USING_CONSOLE is disable.
[BSP] Port to NuMicro M051 Series support for Nuvoton corp.
    1. adapt to M052xDN/xDE, M054xDN/xDE, M058xDN/xDE, M0516/xDN/xDE.
    2. support heap memory management.
Port to gcc and fix keil project
Merge pull request #384 from bright-pan/master

[BSP] Port to NuMicro M051 Series support for Nuvoton corp and fix compile warning
Merge branch 'master' of github.com:RT-Thread/rt-thread