hardware capabilities. This is useful to detect bugs in the
implementation. For the moment only the PCIe link is tested.

* The integer versions of messages_write can take a unit argument.
* Converted some output to use messages_write and unit_megabytes.

type size, so it was not working properly for complex variables.

* Some PUSH/POP's and Doxygen comments.

* Checking documentation even further: the distinction between an explicit-shape [(a:b)] and an assumed-shape [(a:), (:)] array is only in whether the upper bound is specified. Thus, I can put back most of r9394 provided I just specify the lower bound.
* A trivial indentation improvement.

* Added a check for memory leaks in the OpenCL code.

Removing redundant 'error' or 'warning' at the beginning of error/warning messages, and making oscillator_strength use our standard framework for messages.

* The complex version of clSetKernelArg is now used by zaxpy.

* Now the poisson solver is applied without extra copies.

equation. For the moment the implementation is slow as data copied
to/from GPU memory at each step.

* Mismatched push/pop's.

* Added a scalar version of clCreateContext.

receives the number of entries as argument, they can be obtained from
the array properties.

* Added a scalar interface for clGetDeviceIDs and clGetPlatformIDs.

* Added a check for the device and platform id numbers.