Feature request: Allow universal run path for primary script

With a default install, gitlogg expects to be running in the root directory of the project, with a relative path above the scripts directory:

> ./gitlogg.sh
bash: ./scripts/gitlogg-generate-log.sh: No such file or directory

In this issue I propose that gitlogg development invest in a universal CLI tool, requiring some degree of path recognition or explicit sourcing is implemented so that gitlogg can be run anywhere a user would like.

Suggestion 1: command-line arg specified path that explicitly sources the location of the helper scripts
Suggestion 2: install gitlogg in a userland location such as /usr/local/ with explicit paths to that install location
Suggestion 3: packaging of the helper scripts and libraries into a single cli tool