Use own modal instead of alert for symptom info

components/cycle-day/symptoms/info-symptom.js

@@ -0,0 +1,22 @@
+import React from 'react'
+import { ScrollView, View, TouchableOpacity } from 'react-native'
+import Icon from 'react-native-vector-icons/SimpleLineIcons'
+import AppText from '../../app-text'
+import labels from '../../../i18n/en/symptom-info.js'
+import styles, {iconStyles} from '../../../styles/index'
+
+export default function InfoSymptom(props) {
+  return (
+    <View style={styles.infoPopUpWrapper}>
+      <View style={styles.dimmed}></View>
+      <View style={styles.infoPopUp}>
+        <TouchableOpacity onPress={props.close} style={styles.infoSymptomClose}>
+          <Icon name='close' {...iconStyles.infoPopUpClose}/>
+        </TouchableOpacity>
+        <ScrollView style={styles.infoSymptomText}>
+          <AppText>{labels[props.symptom].text}</AppText>
+        </ScrollView>
+      </View>
+    </View>
+  )
+}