Shared library and installation

[remicollet]

Please provide configure option to allow

• installation prefix (ex: /usr)
• include directory (ex: /usr/include/njs)
• library directory (ex: /usrs/lib64)
• shared library (on/off)
• static library (on/off)

So this can be used as all libraries
allowing unit to use it, without having to rebuild it on each version
and also reducing unit executable size (grow from ~480KB to ~1300KB with the static library)

[jirutka]

@xeioex, does njs version number reflect ABI compatibility of libnjs? For example, are all 8.1.x ABI compatible from the point of view of a program dynamically linking libnjs?

[xeioex]

@jirutka

No, unfortunately it does not. That is why 0 is the major version.

We added and removed some functions between 0.8.0 and 0.8.10.