Replace hardcoded paths with configurable ones

Replace hardcoded paths with configurable ones

This patchset aims to ease the packaging of InspIRCd for a system-wide installation scenario.

Changes in detail:
configure: Add the options --log-path and --data-path
m_ssl_gnutls, openssl: Change the hardcoded "conf/" to the existent CONFIG_PATH macro
m_xline_db: Make the location of xline.db configurable. It will use --data-path as default value, but this can be
changed using the configuration files.