container append location is now optional, removed dependencies on jquery

The container append location argument will default to the entire container area if it is not specified.
The widget-base.js had a dependecy on jquery solely for $.isArray, I replaced it by Array.isArray which is in ECMAscript 1.8.5 and above.
added linegraph spec tests to index.html

used before and after functions to create the div and container for the linegraph and remove it once it wasn't needed.
also removed unneeded scripts.
linegraph can append child widgets before or after the data

It is best to append before widgets to the linegraph before the linegraph itself is appended to anything (actually before it gets drawn). Although it should work in either case, appending them after is expensive.
Merge pull request #32 from mlippert/widget-refactor

container append loc default, linegraph "preprend" and some test work