Use GIT commit ids instead of SVN revision numbers.
* configure.ac: Remove SVN revision number tracking. Replace by GIT commit ids. (GPGOL_FORMS_REVISION): New. (GIT_COMMIT_DECIMAL): New. (BUILD_TIMESTAMP): Base version number on the decimalised 4 hex digit commit id. * src/common.h (opt): s/svn_revision/git_commit/. * src/main.c (read_options): Read gitCommit instead of svnRevision. (write_options): Use git_commit. * src/olflange.cpp (GpgolExt): Use GPGOL_FORMS_REVISION to trigger forms installation.