Split manual.js into more files and apply grunt-js.

src/assets/js files are thematically splited.
grunt-js plugin is used in order to combine js files into one all.js.
grunt-js plugin is used in order to minify combined js file into
all.min.js.
IMPORTANT: because grunt-js has incompatible reference to google's
guava, so minifyjs.gradle build file is executed as separate GruntBuild
file.

HTML files for manual as well as Javadoc API reference to all.min.js
file.
Split manual.js into more files and apply grunt-js.

src/assets/js files are thematically splited.
grunt-js plugin is used in order to combine js files into one all.js.
grunt-js plugin is used in order to minify combined js file into
all.min.js.
IMPORTANT: because grunt-js has incompatible reference to google's
guava, so minifyjs.gradle build file is executed as separate GruntBuild
file.

HTML files for manual as well as Javadoc API reference to all.min.js
file.
Remove grunt-js reference from ratpack-manual build.
Merge branch 'master' of https://github.com/zedar/ratpack
Remove grunt-js reference from ratpack-manual.
Clean code.
Merge pull request #534 from zedar/master

Split manual.js into seperate JS files. Combine and minify JS with grunt-js plugin