- refine build dir to avoid collisions with php5 package variants
- properly install headers to location where depended packages look for it

Signed-off-by: Michael Heimpold <mhei@heimpold.de>

Some PECL modules (possibly also php modules) depend on
special load order, otherwise loading the module will fail
due to unresolvable symbols.

This changeset introduces a very simple compile-time defined
order by specifying a prefix for the ini file with the load
directive. If not given, it uses a default value.

It also updates all current pecl module packages to take
this new approach.

Signed-off-by: Michael Heimpold <mhei@heimpold.de>

This is the php7 version of php5-pecl-propro package.

Signed-off-by: Michael Heimpold <mhei@heimpold.de>