Include these methods in the "Code.gs" file of the "Script editor" of your Google Spreadsheet Bot

Code.gs

function getWeather(zip, additionalText) {
  var response = UrlFetchApp.fetch("http://api.poncho.is/weather/forecast/"+zip)
    , obj      = JSON.parse(response.getContentText())
  ;
  
  return [ [obj.data.body+additionalText, obj.data.media] ]
}

/*
 * Retrieves the URL to the active spreadsheet
 * 
 * Note: Cannot be called from HTTP context as SpreadsheetApp.getActiveSpreadsheet() == null
 */ 
function getUrl() {
  return "http://docs.google.com/spreadsheets/d/" + SpreadsheetApp.getActiveSpreadsheet().getId();
}

/*
 * Called in template spreadsheet to make the sheet id available to http requests
 */
function setSpreadsheetId() {
  var sheetId= SpreadsheetApp.getActiveSpreadsheet().getId()
  PropertiesService.getScriptProperties().setProperties({ spreadsheet_id: sheetId });
  return sheetId;
}

/*
 * Returns the spreadsheet ID as defined in script properties
 */
function getSpreadsheetId() {
    return PropertiesService.getScriptProperties().getProperty('spreadsheet_id');
}

/*
 * Lookup a text value by the regular expression column and compute the response value
 *
 * @param { String } spreadsheet_id - pass null to use active sheet or id from properties. 
 * @param { String } text - The text to use for computation.
 * @param { Object } vars - Substitution variables ( e.g. { key: "subthis" } would 
 *                          replace occurrences of %key% with subthis)
 */
function lookupAndCompute(spreadsheet_id, text, vars) {  
  var ss      = spreadsheet_id 
                  ? SpreadsheetApp.openById(spreadsheet_id) //if we pass it in just use it
                  : (
                      //get the active sheet or the one defined in script properties
                      SpreadsheetApp.getActiveSpreadsheet() || SpreadsheetApp.openById(getSpreadsheetId()) 
                    )
    , matches = ss.getSheetByName("Matches")
    , logs    = ss.getSheetByName("Logs")
    , rows    = matches.getRange(2, 1, matches.getLastRow(), matches.getLastColumn())
    , conv    = SheetConverter.init(ss.getSpreadsheetTimeZone(), ss.getSpreadsheetLocale())
    , re, reMatches, row, key
  ;
   
  for(var i=1; i<=rows.getNumRows(); i++) {
    re = rows.getCell(i, 1).getValue();
    
    //skip empty rows
    if(!re) {
      continue;
    }
       
    //ignore regex errors
    try {
      re = new RegExp(re, "i");
      reMatches = text.match(re);
    } catch(e) {
      continue;
    }

    if(reMatches) {
      //make sure formatting is right
      row =  conv.convertRange(rows)[i-1];
      for(var i=0; i<reMatches.length; i++) {
        
        //handle unicode quotation marks
        match = reMatches[i]
          .replace(/[\u2018\u2019]/g, "'")
          .replace(/[\u201C\u201D]/g, '"')
          .replace(/"/g, '""')
        ;
        
        row[1] = row[1].replace(new RegExp('\\\\'+i,'g'), match);
      }
      
      //replace dynamic variables
      for(var key in vars) {
        if(vars.hasOwnProperty(key)) {
          val = vars[key];
          for(var j=0; j<row.length; j++) {
            if(row[j])
              row[j] = row[j].replace(new RegExp('%'+key+'%', 'ig'), val);
          }
        }
      }
      
      //add some relevant details text, datetime
      row.unshift(text);
      row.unshift((new Date()).toUTCString());
      idx = logs.appendRow(row).getLastRow();

      //again make sure formatting is right
      row = conv.convertRange(logs.getRange(idx, 1, 1, logs.getLastColumn()));
      return { row: row[0] };
    }
  }

  return "done";  
}