Add string:jaro_similarity/2 #332

Job	Run time
Build Erlang/OTP (64-bit)	15m 30s
Event File	2s
Build Erlang/OTP (iOS)	8m 36s
Build Erlang/OTP (macOS)	7m 53s
Build Erlang/OTP (Types and Flavors)	0s
Build Erlang/OTP (32-bit)	8m 31s
Build Erlang/OTP (cross-compile)	13m 39s
Build Erlang/OTP (Windows)	13m 27s
Build and check documentation	8m 5s
Run static analysis	7m 0s
Build Erlang/OTP (clang)	5m 40s
Test Erlang/OTP (stdlib)	34m 34s
Release Erlang/OTP	0s
Test Erlang/OTP (system)	8m 37s
	2h 11m 34s

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