Update crate version for 3.6.2 release

Update crate version for release

Fix documentation test in graphics module

Merge pull request arrayfire#159 from arrayfire/devel

v3.5.0 devel to master

Merge pull request arrayfire#127 from arrayfire/devel

v3.4.3 devel to master

Merge pull request arrayfire#112 from arrayfire/devel

v3.4.2 devel to master

Merge pull request arrayfire#96 from arrayfire/devel

v3.4.1 devel to master

Removed unused imports in random module

v3.3.1 Release

Update README with v3.3.0 release information