Target compilation strategy names are confusing / misleading

[prokod]

As part of the discussion over #140 it is apparent that targetCompatibility.strategy naming is not user friendly.
To improve on that - change strategy names as follows:

DEFAULT -> DEFAULT
SMART -> MAX
STRICT -> STRICT

To highlight in documentation the strategy is actually as follows:

DEFAULT -> TOOLCHAIN_OR_DEFAULT
SMART -> TOOLCHAIN_OR_MAX
STRICT -> TOOLCHAIN_OR_FAIL