Update blockchain-spv to version 3.1.2 🚀

[greenkeeperio-bot]

Hello lovely humans,

blockchain-spv just published its new version 3.1.2.

State	Update 🚀
Dependency	blockchain-spv
New version	3.1.2
Type	dependency

This version is not covered by your current version range.

Without accepting this pull request your project will work just like it did before. There might be a bunch of new features, fixes and perf improvements that the maintainers worked on for you though.

I recommend you look into these changes and try to get onto the latest version of blockchain-spv.
Given that you have a decent test suite, a passing build is a strong indicator that you can take advantage of these changes by merging the proposed change into your project. Otherwise this branch is a great starting point for you to work on the update.

Do you have any ideas how I could improve these pull requests? Did I report anything you think isn’t right?
Are you unsure about how things are supposed to work?

There is a collection of frequently asked questions and while I’m just a bot, there is a group of people who are happy to teach me new things. Let them know.

Good luck with your project ✨

You rock!

🌴

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The new version differs by 19 commits .

• 9380fe3 3.1.2
• 83d4221 Blockchain/putIfNotFound: don't put block if it was found
• 3897473 3.1.1
• af58b11 Blockchain: fixed method name typo
• 745400c 3.1.0
• 9fe89fd Blockchain: added 'estimatedChainHeight' helper function for syncing
• 092c024 HeaderStream: added 'sync' option, for ensuring blocks aren't pushed until committed into db
• dfd5ee8 3.0.1
• dc4d51c Blockchain: make sure origin and and checkpoint blocks get added to height index
• 4f15aa7 Fixed tests for ES5 JS engines
• c4baeb7 3.0.0
• 9bdd498 Added HeaderStream test for reorging while initializing
• 9d9c493 Blockchain: don't unlink headers from losing forks
• f63b196 Fixed reorg test to do reorg after stream initializes
• a2c7c75 Fixed standard style check in test script

There are 19 commits in total. See the full diff.

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This pull request was created by greenkeeper.io.

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