improve the parsing of concepts in text

[thhomas]

{$CONCEPT} and {CONCEPT} parsing handled. improve parsing of concept for TIME_PERIOD when multiple values returns a text like "start_value - end_value" enclosed a yaml for testing:

---
DashID: COVID
Rows:
-
    Row: 0
    chartType: TITLE
    Title: "COVID-19 Dashboard"
    Subtitle: 
    Unit: 
    unitLoc: 
    Decimals: 
    LabelsYN:
    legendConcept: 
    legendLoc: 
    xAxisConcept: 
    yAxisConcept: 
    downloadYN: 
    dataLink: 
    metadataLink: 
    DATA: 
-
    Row: 1 
    chartType: LINES, double
    Title: "Number of COVID-19 cases"
    Subtitle: "{$TIME_PERIOD}" 
    Unit: 
    unitLoc: 
    Decimals: 0
    LabelsYN: No
    legendConcept: GEO_PICT
    legendLoc: BOTTOM
    xAxisConcept: TIME_PERIOD
    yAxisConcept: OBS_VALUE
    downloadYN: 
    dataLink: 
    metadataLink: 
    DATA: "https://stats-sdmx-disseminate.pacificdata.org/rest/data/SPC,DF_COVID,1.0/M..CASES?lastNObservations=13&dimensionAtObservation=AllDimensions"
-
    Row: 2 
    chartType: LINES, double
    Title: "Number of COVID-19 deaths"
    Subtitle: "{$TIME_PERIOD}" 
    Unit: 
    unitLoc: 
    Decimals: 0
    LabelsYN: No
    legendConcept: GEO_PICT
    legendLoc: BOTTOM
    xAxisConcept: TIME_PERIOD
    yAxisConcept: OBS_VALUE
    downloadYN: 
    dataLink: 
    metadataLink: 
    DATA: "https://stats-sdmx-disseminate.pacificdata.org/rest/data/SPC,DF_COVID,1.0/M..DEATHS?lastNObservations=13&dimensionAtObservation=AllDimensions"