radically changed the headless build using InternalBuilder

Change-Id: I95e5d4d8a99a517930a88e03f46d6a4952da2a20
also perform a clean build

Change-Id: Ic92d9aa0fd5e1c3e3e38e5665a9c7af346e401a0
include xdoc feature in the bootstrap-build

Change-Id: I6d067ed61ed638b8136621fed934082addeeb88b
remove xdoc generated files from the repository

Change-Id: Ib61c6fb70ae2f9e6d33e119fb95b19f4d3275582
use xdoc feature in boostrap-build.launch

instead of single xdoc bundles

Change-Id: I3209a00b7f55838793528d72dddc541846c4469b
moved some utils in the tests and removed unused code

Change-Id: I879b4485f0f5f5bebd0b14e307e5df509b72ab96
added a performance test

Change-Id: Ic4b1cf435fa5888e2a56721f2c4c93a00cf43899
fixed some code coverage

Change-Id: I5bf23c6ae69cb7ede350a9958a9034269887bd43
XsemanticsUtils is a @Singleton

Change-Id: Ic3539aad8e62f09be2bf81708280b99648007d68
caching in XsemanticsUtils

Change-Id: I3bb63a4d206fd1dfcbd10a4fbe0a5a33a6671c20