Revert "Revert "Revert "Fixed issues with moveMotor method."""

This reverts commit 51eec4aa08878eca8197d35acfd6305eec9908c5.
Revert "Added preferred length and motor speeds. Required for constant speed"

This reverts commit 63c9cbbb2ee3f06498a0cf67b5ab225ffd462ed3. Since the functions that were added already exists in tgLinearString class.