Add benchmarks for rotate and rotate_copy

Added compute and stl benchmarks for rotate() and rotate_copy()
Merge pull request #68 from roshanr95/rotate_benchmarks

Add benchmarks for rotate and rotate_copy
Add test for inner_product() with counting_iterator
Check binary status in program::create_with_binary()
Check for empty strings in get_object_info()
Fix BOOST_COMPUTE_FUNCTION() with non-default-constructible types
Add buffer::clone() method
Unique algorithm

Added unique() algorithm, tests and benchmarks. Removed unused variable
in scan_on_gpu() to remove warnings
Merge pull request #74 from ddemidov/master

Fixing several warnings given by pedantic g++-4.8.2
Merge pull request #75 from roshanr95/unique

Unique algorithm
Fix bug in copy-constructor for wait_list
Use lcov to generate coverage info for coveralls.io
Add mandelbrot example
Enable compiler warnings for Travis-CI
Add get_nvidia_compute_capability() function
Copy multiple values per thread in copy_on_device()
Fix unique benchmarks
Merge pull request #80 from roshanr95/unique_benchmarks

Fix unique benchmarks
Improve reduce() performance with generic iterators
Fix ambiguous member template warning with clang