Allow pre-compilation of rules conditions

Description

Adds functionality to pre-compile rules' conditions in order to speed up evaluation times. Putting it simply: it adds a middleware component that intercepts rules loaded from the data source or being written to the data source, and compiles them to a lambda expression. The resultant lambda expression is stored on the data source, thanks to the new IConditionNode<TConditionType>.Properties dictionary property, which enables to store the compiled lambda expression. This compiled lambda expression is then loaded from the data source avoiding re-compiling the rules' conditions again. This development also includes a conditions eval engine prepared to evaluate compiled rules.

A new project with a Benchmark.Net implementation was already added to measure some performance numbers. Unfortunately, I was unable to assess the improvement of this implementation vs. the master codebase. I'm including the performance numbers taken from the implementation as-is for your consideration.

Benchmark	Method	EnableCompilation	Mean (ns)	Error (ns)	StdDev (ns)	Skewness	Kurtosis	BranchInstructions/Op	BranchMispredictions/Op	Gen0	Allocated (KB)
1 - Test rule (1 rule, 1 condition)	RunAsync	FALSE	660,5	3,08	2,88	-0,0707	1,751	2122	2	0,1287	1,59
1 - Test rule (1 rule, 1 condition)	RunAsync	TRUE	584,1	3,69	3,27	-0,0777	2,724	1841	2	0,1402	1,72
2 - Songs (2 rules, various conditions)	RunAsync	FALSE	2003,9	9,34	8,73	-0,3514	2,111	7089	8	0,3166	3,92
2 - Songs (2 rules, various conditions)	RunAsync	TRUE	958,8	5,35	5,01	-0,2135	2,135	3619	2	0,1564	1,93
3 - Poker rules (100+ rules, various conditions)	RunAsync	FALSE	39190	263	246	-0,166	2,221	141307	239	6,2866	77,37
3 - Poker rules (100+ rules, various conditions)	RunAsync	TRUE	20910	148	139	0,676	2,303	75102	65	2,9297	36,15

Here's how they compare:

Benchmark	Time taken [Interpreted] - ns	Time taken [Compiled] - ns	Time taken [Interpreted vs. Compiled] - % gain	Memory [Interpreted] - KB	Memory [Compiled] - KB	Memory [Interpreted vs. Compiled] - % gain
1	660,50	584,1	11,57%	1,59	1,72	-8,18%
2	2003,9	958,8	52,15%	3,92	1,93	50,77%
3	39190	20910	46,64%	77,37	36,15	53,28%

Related to #49.

Change checklist

[x] Code follows the code rules guidelines of this project
[x] Commit messages follow the commit rules of this project
[x] I have self-reviewed my changes before submitting this pull request
[x] I have covered new/changed code with new tests and/or adjusted existent ones
[x] I have made changes necessary to update the documentation accordingly -> will adjust the wiki after merge to master.

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Farfetch / rules-framework