bootstrap.xml parsing and handling

[shizmob]

This patchset adds full support for parsing and handling of prop/bootstrap.xml as alternative to the command-line parameter configuration of launcher itself.

It adds the following command line options:

• -C: path to bootstrap.xml (default: prop/bootstrap.xml)
• -Z: selector in bootstrap.xml to use. Required for bootstrap.xml parsing to take place.

If given a valid bootstrap.xml and selector, launcher will:

• Use avs-config.xml path from it by default
• Use ea3-config.xml path from it by default
• Use AVS and std heap size from it by default
• Use module path from it by default
• Use module parameters from it it in lieu of app-config.xml
• Setup initialising default files specified in it
• Update parsed AVS config with log node and some default parameters, like bootstrap

As indicated by the @573 ordinal number, all avs_fs_* imports need to be checked, except for AVS 2.15.8.

This MR depends on #253 for its added property definitions.

[icex2]

Closing as I picked up the work and continue driving it from a new PR: https://github.com/djhackersdev/bemanitools/pull/272