Merge pull request #57 from brainsail/develop

Added recored type selector.
fixes zone list scrolling over the header
remove ability to delete SOA or NS records
clean up record type filter
disable selecting a different record type when editing a record
add pendingChanges flag to record to prevent duplicate new records when editing a new record
closes #50 update README
bump to version 1.0.0
Merge branch 'release/1.0.0' into develop