Update ReadMe

* List library dependencies.
* Remove "Specific: Linux" section. I can only assume that zlib1g-dev
  is/was a package for a specific distribution.
* "Configuring your build" section:
  - Mention that a change of the cross-compilation tools may require
    re-configuring.
  - Update the configure calls as required since the package management
    merge.
* "Building via Jam" section:
  - Use build profiles.
  - Consequently use "-q".