Make entity recognizers to be simple Recognizer

[chon219]

Fixes #3039
Fixes #3044

Description

EntityRecognizers are simple wrappers around TextAnalytics APIs, but currently are only usable from within RegExRecognizer via the EntityRecognizerSet.
This delta makes all EntityRecognizers full blown recognizers, allowing them to be composed like any other recognizer in the system.

Specific Changes

• Make EntityRecognizer class
• Added ChannelMentionEntityRecognizer
• Exposed EntityRecognizerSet in AdaptiveComponentRegistration
• Updated @microsoft/recognizers-text-suite to latest version
• Renamed protected method recognize in all EntityRecognizers to avoid conflicts with recognize method from parent EntityRecognizer
• Change mapping of text recognizer ModelResult => entity structure to make the end + 1
• Filter seed text entities

Testing

Ported tests from C#.

[coveralls]

Pull Request Test Coverage Report for Build 405236527

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 2 unchanged lines in 2 files lost coverage.
• Overall coverage increased (+0.04%) to 84.431%

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Files with Coverage Reduction	New Missed Lines	%
libraries/botbuilder-core/src/recognizerResult.ts	1	88.89%
libraries/botbuilder-dialogs-adaptive/src/recognizers/entityRecognizers/entityRecognizerSet.ts	1	91.18%

Totals
Change from base Build 401718224:	0.04%
Covered Lines:	17593
Relevant Lines:	19910

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💛 - Coveralls

[joshgummersall]

Couple of small changes, looks good though! Nice use of reduce and ??=.