ZCLDB: Add level control cluster attribute 0x000f found on IKEA lights
<attribute id = "0001" name="Remaining Time" type="u16" range="0x0000,0xffff" access="r" required="o" default="0x0000">
<description>The RemainingTime attribute represents the time remaining until the current command is complete - it is specified in 1/10ths of a second.</description>
</attribute>
+ <attribute id = "0x000f" name="Unknown" type="bmp8" access="rw" required="o">
+ <description>IKEA specific.</description>
+ </attribute>
<attribute id = "0010" name="OnOff Transistion Time" type="u16" range="0x0000,0xffff" access="rw" required="o" default="0x0000">
<description>The OnOffTransitionTime attribute represents the time taken to move to or from the target level when On of Off commands are received by an On/Off cluster on the same endpoint. It is specified in 1/10ths of a second. The actual time taken should be as close to OnOffTransitionTime as the device is able.</description>
</attribute>
