Internalize Environment services and use Key as name

[lahma]

Checked the usual suspects seems that Environment and related APIs can be hidden, allows using Key and only one to suffer a small hit is ObjectEnvironment which is used by with and its usage is discouraged.

[lahma]

Jint.Benchmark.DromaeoBenchmark

Diff	Method	Toolchain	FileName	Mean	Error	Allocated
Old	Run	Default	dromaeo-3d-cube	22.317 ms	0.0417 ms	6284.06 KB
New		Default		23.176 ms (+4%)	0.0239 ms	6284.27 KB (0%)
Old	Run	Default	dromaeo-core-eval	4.356 ms	0.0225 ms	311 KB
New		Default		4.063 ms (-7%)	0.0129 ms	311.47 KB (0%)
Old	Run	Default	dromaeo-object-array	45.259 ms	0.4791 ms	100362.98 KB
New		Default		45.056 ms (0%)	0.2089 ms	100362.98 KB (0%)
Old	Run	Default	droma(...)egexp [21]	157.635 ms	1.7532 ms	161417.29 KB
New		Default		161.615 ms (+3%)	1.2240 ms	165555.16 KB (+3%)
Old	Run	Default	droma(...)tring [21]	334.605 ms	13.3655 ms	1321325.97 KB
New		Default		318.525 ms (-5%)	12.3468 ms	1321588.91 KB (0%)
Old	Run	Default	droma(...)ase64 [21]	51.122 ms	0.1005 ms	6044.92 KB
New		Default		51.766 ms (+1%)	0.0552 ms	6044.57 KB (0%)
Old	Run	Default	dromaeo-3d-cube	21.986 ms	0.0248 ms	5994.73 KB
New		Default		21.807 ms (-1%)	0.0619 ms	5994.94 KB (0%)
Old	Run	Default	dromaeo-core-eval	4.174 ms	0.0132 ms	298.44 KB
New		Default		4.093 ms (-2%)	0.0076 ms	298.91 KB (0%)
Old	Run	Default	dromaeo-object-array	44.652 ms	0.3315 ms	100324.02 KB
New		Default		45.010 ms (+1%)	0.1634 ms	100324.02 KB (0%)
Old	Run	Default	droma(...)egexp [21]	154.841 ms	1.2736 ms	172295.65 KB
New		Default		160.887 ms (+4%)	1.5880 ms	165940.47 KB (-4%)
Old	Run	Default	droma(...)tring [21]	334.037 ms	13.4039 ms	1321149 KB
New		Default		366.460 ms (+10%)	14.3587 ms	1321478.8 KB (0%)
Old	Run	Default	droma(...)ase64 [21]	57.075 ms	0.1819 ms	5958.77 KB
New		Default		52.097 ms (-9%)	0.1542 ms	5958.35 KB (0%)