Allows mongodb host to be configured, fixes some problematic requires and non-dev dependencies

[Laurian]

Adds:

• MongoDB host can be specified as env variable DBHOST, defaults to localhost

Fixes:

• require calls like require("../node_modules/superscript/lib/history") to require("superscript/lib/history")which will allow the editor to function if it is a dependency in a project that already depends on superscript
• dependencies declared under devDependencies which are runtime ones actually and will break again when using the editor as a dependency in another project
• (byproduct) extra whitespace at the end of the lines

[silentrob]

Thank you! This is a great addition!