build manuals moved here from osmo-gsm-manuals.git
Moved to doc/manuals/, with full commit history, in preceding merge commit.
Now incorporate in the build system.
Build with:
$ autoreconf -fi
$ ./configure --enable-manuals
$ make
Shared files from osmo-gsm-manuals.git are found automatically if
- the repository is checked out in ../osmo-gsm-manuals; or
- if it osmo-gsm-manuals was installed with "make install"; or
- OSMO_GSM_MANUALS_DIR is set.
Related: OS#3385
Change-Id: I7d1226d3865da9595b730b716a8d4ba07be1e0d5