[#525] avoid using `instanceOf` when possible

typically on object child that were created/replicated using the
deepcopy function.
[#521] added basic type check for the `me.Vector2d` constructor

this will help prevent breaking the internal global translation buffer
(see related ticket for more details)
[#525] fixed some linting issues
small look refresh for documentation : more flat and flashy to be more in line with the "melonJS" green and  blog color scheme
last leftover tidbits from the 1.0.2 branch
Merge branch 'master' of https://github.com/melonjs/melonJS