Add experiments grunt task, for convenience

[prushforth]

This will only be useful if you have an experiments repo as a sibling repo to your web-map-custom-element (this) repo. Note this would potentially really bad if you had an experiments directory that wasn't the intended target of this task as a sibling directory to the directory from which this task executes, because it deletes the dist folder in that directory and replaces it with the built dist folder from web-map-custom-elements.

To build and copy the built 'dist' folder to the experiments repo:

$ grunt experiments
Running "clean:experiments" (clean) task
>> 1 path cleaned.

Running "clean:dist" (clean) task
>> 1 path cleaned.

Running "copy:main" (copy) task
PATCHING:  node_modules/proj4/dist/proj4-src.js
PATCHING:  node_modules/proj4leaflet/src/proj4leaflet.js
MODIFYING:  index.html
Copied 4 files

Running "copy:images" (copy) task
Copied 5 files

Running "copy:experiments" (copy) task
Created 1 directory, copied 4 files

Running "jshint:files" (jshint) task
>> 39 files lint free.

Running "rollup:main" (rollup) task

Running "uglify:dist" (uglify) task
>> 7 sourcemaps created.
>> 7 files created 1.09 MB → 441.97 kB

Running "cssmin:combine" (cssmin) task
>> 1 file created. 34.3 kB → 25.2 kB

Running "clean:tidyup" (clean) task
>> 3 paths cleaned.

Running "copy:experiments" (copy) task
Created 1 directory, copied 16 files

Done.

$