Use less @Import from classpath

[arey]

Right now, lesscss maven plugin does NOT support @import from classpath. See marceloverdijk/lesscss-maven-plugin#72
In the pom.xml of the springboot branch, there is workaround in the pom.xml unpacking the bootstrap on-the-fly. Remove this plugin config when the issue is resolved OR a better resolution is found.
The gabrysbiz/lesscss-extended-compiler#2 has been closed.

[arey]

Use wro4j instead of lesscss plugin: 131a588