Merge pull request #1058 from code-dot-org/finished

finished -> levelbuilder
Write custom levels to individual json-formatted .level files
add error for multiple level files with same name
naming changes
Merge pull request #1064 from code-dot-org/finished

finished -> levelbuilder
Merge pull request #1067 from code-dot-org/finished

finished -> levelbuilder
Merge pull request #1073 from code-dot-org/finished

finished -> levelbuilder
level changes
level changes
Merge pull request #1060 from code-dot-org/custom_level_per_file

Write custom levels to individual json-formatted .level files
updated custom levels
levelbuilder updates
add custom level files
Merge pull request #1076 from code-dot-org/level-builder

Merge Level builder changes into finished