Fix: Don't put a extra semicolon in bower

Only include a comma when bowerDependencies.length !== 0
Fix usage of useref, wiredep with bower_components
Merge pull request #98 from eseceve/fix-bower

Don't put a extra comma in bower
Merge pull request #96 from eleven-labs/fix

Fix usage of useref, wiredep with bower_components
Merge branch 'master' of https://github.com/Swiip/generator-gulp-angular