Fixes typos throughout the codebase (#561)

dapps/valuetransfers/packages/tangle/payloadmetadata.go

dapps/valuetransfers/packages/tangle/payloadmetadata_test.go

dapps/valuetransfers/packages/tangle/tangle_test.go

dapps/valuetransfers/packages/tangle/transactionmetadata.go

packages/binary/datastructure/orderedmap/orderedmap.go

packages/binary/datastructure/orderedmap/orderedmap_test.go

.../binary/messagelayer/messagerequester/messagerequester.go

packages/binary/messagelayer/tangle/messagemetadata.go

packages/metrics/events.go

plugins/analysis/dashboard/fpc_conflict.go

plugins/dashboard/explorer_routes.go

plugins/metrics/global_metrics.go

plugins/prometheus/autopeering.go

plugins/prometheus/process.go

plugins/webapi/info/plugin.go

plugins/webapi/message/plugin.go

plugins/webapi/value/attachments/handler.go

plugins/webapi/value/gettransactionbyid/handler.go

plugins/webapi/value/unspentoutputs/handler.go

tools/integration-tests/tester/tests/common/common_test.go