* collector: Unwrap glob textfile directories
* collector: Store full path in mtime's file label
The point is to avoid duplicated gauges from files with the same name in
different directories.
This introduces support for exporting from multiple directories matching
given pattern (e.g. `/home/*/metrics/`).
Signed-off-by: Kiril Vladimirov <kiril@vladimiroff.org>
* remove injection hook for textfile metrics, convert them to prometheus format
* add support for summaries
* add support for histograms
* add logic for handling inconsistent labels within a metric family for counter, gauge, untyped
* change logic for parsing the metrics textfile
* fix logic to adding missing labels
* Export time and error metrics for textfiles
* Add tests for new textfile collector, fix found bugs
* refactor Update() to split into smaller functions
* remove parseTextFiles(), fix import issue
* add mtime metric directly to channel, fix handling of mtime during testing
* rename variables related to labels
* refactor: add default case, remove if guard for metrics, remove extra loop and slice
* refactor: remove extra loop iterating over metric families
* test: add test case for different metric type, fix found bug
* test: add test for metrics with inconsistent labels
* test: add test for histogram
* test: add test for histogram with extra dimension
* test: add test for summary
* test: add test for summary with extra dimension
* remove unnecessary creation of protobuf
* nit: remove extra blank line
