add usms product

[yufeiminds]

FEATURE:

• Add SendUSMSMessage as public api
• Add GetUSMSSendReceipt as public api
• Add CreateUSMSSignature as public api
• Add QueryUSMSSignature as public api
• Add UpdateUSMSSignature as public api
• Add DeleteUSMSSignature as public api
• Add CreateUSMSTemplate as public api
• Add QueryUSMSTemplate as public api
• Add UpdateUSMSTemplate as public api
• Add DeleteUSMSTemplate as public api

[codecov-io]

Codecov Report

Merging #14 into master will not change coverage.
The diff coverage is n/a.

@@ Coverage Diff @@## master #14 +/- ##
=======================================
Coverage 96.16% 96.16% =======================================
Files 18 18 Lines 521 521 =======================================
Hits 501 501 Misses 20 20

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