Adds p5.Vector documentation
Adds additional documentation for static/non-static p5.Vector methods
Adds inline example for angleBetween
Adds additional documentation to non-static/static methods
Refines description of p5.Vector static/non static methods
implimented loading screen functionality as per feature request in issue #317. Also added a basic  example as to how it can be implimented into a project.
merged upstream with loadingscreen update
fixed typo in docs
fixed spelling typo
ran grunt to make sure most recent files have been compiled / minified
updating size fxn
need to check for null, otherwise it will throw error on first run when using instance mode
class is reserved word in JavaScript standard
Merge remote-tracking branch 'upstream/master'
minor
removing premature httpget test
Merge github.com:jshaw/p5.js
merging loading screen
making change this.loadingScreenId to this._loadingScreenId
Merge remote-tracking branch 'upstream/master'