This changes adds support for encoding linear half float hdr intent
inputs. linear color transfer inputs are restricted to half float color
format only to keep it symmetrical with decoder.

fixes #279

Test: ./ultrahdr_app

Recipes associated with building for android target have typo issues.
These are resolved. Also config options supported by the library are
documented.

If opengl is enabled, then add egl and glesv3 libraries in to
Libs.Private list for static linking

also minor documentation updates in sample app and clang-formatting

Test: Build

- updated pre-requistes and side effects
- add support for building shared, static targets (selective)
- improve documentation in cmakelists
- update readme.md

- restrict install and uninstall targets to Un*x
- improvements in cmakelists.txt and pc template
  (thanks to milos)
- Fixes #95
- Updates to readme.md

Test: make install

Updated sample application and unit tests for new interface

Test: ./ultrahdr_unit_test

Co-authored-by: Aayush Soni <aayush.soni@ittiam.com>
Change-Id: I99d8ada4b0850630bc14a1c33a764a00e6f09e9f

source files are restructured according to coding guidelines

library files are moved to lib/ folder and sample application is
moved to examples/ folder

Added building commands

Update README.md to remove the section on cmake build as some dependencies are not yet fully resolved.