Update badger to latest version

This commit brings the following changes from badger

c45d966 Fix assert in background compression and encryption. (#1366)
14386ac GC: Consider size of value while rewriting (#1357)
b2267c2 Restore: Account for value size as well (#1358)
b762832 Tests: Do not leave behind state goroutines (#1349)
056d859 Support disabling conflict detection (#1344)
fd89894 Compaction: Expired keys and delete markers are never purged (#1354)
543f353 Fix build on golang tip (#1355)
a7e239e StreamWriter: Close head writer (#1347)
da80eb9 Iterator: Always add key to txn.reads (#1328)
7e19cac Add immudb to the project list (#1341)
079f5ae DefaultOptions: Set KeepL0InMemory to false (#1345)

go.mod

@@ -16,7 +16,7 @@ require (
 	github.com/blevesearch/segment v0.0.0-20160915185041-762005e7a34f // indirect
 	github.com/blevesearch/snowballstem v0.0.0-20180110192139-26b06a2c243d // indirect
 	github.com/codahale/hdrhistogram v0.0.0-20161010025455-3a0bb77429bd
-	github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20200528205344-e7b6e76f96e8
+	github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20200615081930-c45d966681d4
 	github.com/dgraph-io/dgo/v200 v200.0.0-20200401175452-e463f9234453
 	github.com/dgraph-io/ristretto v0.0.2
 	github.com/dgrijalva/jwt-go v3.2.0+incompatible

go.sum

@@ -78,8 +78,8 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dgraph-io/badger v1.6.0 h1:DshxFxZWXUcO0xX476VJC07Xsr6ZCBVRHKZ93Oh7Evo=
 github.com/dgraph-io/badger v1.6.0/go.mod h1:zwt7syl517jmP8s94KqSxTlM6IMsdhYy6psNgSztDR4=
-github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20200528205344-e7b6e76f96e8 h1:TDpSSjrjipVJHEpcimd7uRYqiIeMc1LsM7p2tgEl+s8=
-github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20200528205344-e7b6e76f96e8/go.mod h1:3KY8+bsP8wI0OEnQJAKpd4wIJW/Mm32yw2j/9FUVnIM=
+github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20200615081930-c45d966681d4 h1:399xipP1BGjp6OJYSrmBw0V4TgIL/wc4xR+8n1HUv5M=
+github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20200615081930-c45d966681d4/go.mod h1:3KY8+bsP8wI0OEnQJAKpd4wIJW/Mm32yw2j/9FUVnIM=
 github.com/dgraph-io/dgo/v200 v200.0.0-20200401175452-e463f9234453 h1:DTgOrw91nMIukDm/WEvdobPLl0LgeDd/JE66+24jBks=
 github.com/dgraph-io/dgo/v200 v200.0.0-20200401175452-e463f9234453/go.mod h1:Co+FwJrnndSrPORO8Gdn20dR7FPTfmXr0W/su0Ve/Ig=
 github.com/dgraph-io/ristretto v0.0.2-0.20200115201040-8f368f2f2ab3/go.mod h1:KPxhHT9ZxKefz+PCeOGsrHpl1qZ7i70dGTu2u+Ahh6E=

worker/server_state.go

@@ -71,6 +71,12 @@ func setBadgerOptions(opt badger.Options) badger.Options {
 	// Do not load bloom filters on DB open.
 	opt.LoadBloomsOnOpen = false
 
+	// Disable conflict detection in badger. Alpha runs in managed mode and
+	// perform its own conflict detection so we don't need badger's conflict
+	// detection. Using badger's conflict detection uses memory which can be
+	// saved by disabling it.
+	opt.DetectConflicts = false
+
 	glog.Infof("Setting Badger Compression Level: %d", Config.BadgerCompressionLevel)
 	// Default value of badgerCompressionLevel is 3 so compression will always
 	// be enabled, unless it is explicitly disabled by setting the value to 0.