[examples] Use `bat-config` instead of `BATINSTALLDIR`

o make -C examples builds all examples
[gitignore] Add bat-config and bat.pc
[examples] Update README files wrt. bat-config
[doc] Update INSTALL, use github markdown and rename it to INSTALL.md
[README] Update and change to markdown format
[doc] Fix doc regarding installation

o add missing file bat.eps
o remove installation instructions from introduction => maintain only INSTALL.md
o add BAT version to tex automatically
o gitignore tex intermediate files
[build] Towards passing `make distcheck`

o INSTALL.md, README.md added to source dist
o test's Makefile only not made is extra source build
o fix header include directory in Makefile.am's
[gitignore] Test results
[introduction] Add missing files to git
[build] Fixed installation of rootmap files

Installation of rootmap files was broken for out-of-tree builds,
also causing "make distcheck" to fail.