DateTime Improvements

[Turnerj]

Multiple different things here for improving performance around the current time access. This is based on the details discussed in this Tweet: https://twitter.com/Nick_Craver/status/1262045129038344192

Currently it is ~22% faster in benchmarking.

Method	Iterations	Mean	Error	StdDev	Median	Ratio	RatioSD	Gen 0	Gen 1	Gen 2	Allocated
CacheTower_MemoryCacheLayer_Direct	1	645.5 ns	3.38 ns	2.64 ns	645.7 ns	0.31	0.00	0.3052	-	-	960 B
LazyCache_MemoryProvider	1	1,897.5 ns	36.76 ns	42.33 ns	1,878.0 ns	0.91	0.02	0.4139	-	-	1304 B
CacheTower_MemoryCacheLayer_ViaCacheStack	1	2,088.9 ns	14.01 ns	12.42 ns	2,089.6 ns	1.00	0.00	0.4730	-	-	1488 B
LazyCache_MemoryProviderAsync	1	2,111.1 ns	15.39 ns	14.40 ns	2,111.7 ns	1.01	0.01	0.4845	-	-	1520 B
EasyCaching_InMemory	1	9,868.3 ns	67.82 ns	63.44 ns	9,853.6 ns	4.72	0.04	1.3580	-	-	4289 B
CacheManager_MicrosoftMemoryCache	1	19,312.1 ns	121.42 ns	113.57 ns	19,252.9 ns	9.25	0.07	2.4719	1.2207	-	7848 B
EasyCaching_InMemoryAsync	1	21,870.8 ns	392.46 ns	347.91 ns	21,848.8 ns	10.47	0.17	2.0142	-	-	6264 B
CacheTower_MemoryCacheLayer_Direct	1000	202,790.5 ns	1,979.25 ns	1,851.39 ns	202,984.7 ns	0.33	0.00	10.4980	-	-	32929 B
CacheTower_MemoryCacheLayer_ViaCacheStack	1000	614,702.3 ns	6,001.12 ns	5,011.21 ns	616,239.8 ns	1.00	0.00	9.7656	-	-	33458 B
LazyCache_MemoryProvider	1000	1,804,438.1 ns	24,963.15 ns	60,763.76 ns	1,783,246.7 ns	3.08	0.16	335.9375	-	-	1064240 B
CacheManager_MicrosoftMemoryCache	1000	1,940,035.3 ns	11,546.63 ns	10,800.72 ns	1,940,122.3 ns	3.16	0.03	87.8906	-	-	279719 B
LazyCache_MemoryProviderAsync	1000	1,988,760.9 ns	14,423.38 ns	12,044.17 ns	1,994,035.9 ns	3.24	0.04	406.2500	-	-	1280245 B
EasyCaching_InMemory	1000	4,516,944.6 ns	45,462.25 ns	40,301.10 ns	4,522,247.3 ns	7.36	0.10	343.7500	-	-	1099413 B
EasyCaching_InMemoryAsync	1000	7,387,677.6 ns	99,594.49 ns	93,160.74 ns	7,371,528.9 ns	11.99	0.18	664.0625	-	-	2068658 B
CacheTower_MemoryCacheLayer_Direct	1000000	203,166,917.9 ns	1,194,781.30 ns	997,696.50 ns	203,064,033.3 ns	0.33	0.00	10000.0000	-	-	32000928 B
CacheTower_MemoryCacheLayer_ViaCacheStack	1000000	614,075,766.7 ns	8,648,199.02 ns	8,089,530.72 ns	613,836,100.0 ns	1.00	0.00	10000.0000	-	-	32002320 B
LazyCache_MemoryProvider	1000000	1,757,410,420.0 ns	12,920,524.91 ns	12,085,867.02 ns	1,758,450,100.0 ns	2.86	0.04	339000.0000	-	-	1064000240 B
CacheManager_MicrosoftMemoryCache	1000000	1,888,174,873.3 ns	18,181,070.11 ns	17,006,584.27 ns	1,893,119,100.0 ns	3.08	0.05	86000.0000	-	-	272009128 B
LazyCache_MemoryProviderAsync	1000000	1,977,939,364.3 ns	11,243,719.15 ns	9,967,264.16 ns	1,980,478,550.0 ns	3.22	0.04	408000.0000	-	-	1280000344 B
EasyCaching_InMemory	1000000	4,571,407,828.6 ns	41,049,432.55 ns	36,389,252.74 ns	4,577,811,250.0 ns	7.44	0.12	349000.0000	-	-	1096213192 B
EasyCaching_InMemoryAsync	1000000	7,430,601,366.7 ns	46,383,876.25 ns	43,387,506.62 ns	7,423,960,300.0 ns	12.10	0.19	663000.0000	-	-	2064400712 B